diff --git a/src/backend/core/api/serializers.py b/src/backend/core/api/serializers.py
index 03a092d6..d280bde6 100644
--- a/src/backend/core/api/serializers.py
+++ b/src/backend/core/api/serializers.py
@@ -152,8 +152,8 @@ class ListDocumentSerializer(BaseResourceSerializer):
         model = models.Document
         fields = [
             "id",
-            "abilities",
             "content",
+            "abilities",
             "created_at",
             "creator",
             "is_favorite",
diff --git a/src/backend/core/api/viewsets.py b/src/backend/core/api/viewsets.py
index 052e2321..fb998be5 100644
--- a/src/backend/core/api/viewsets.py
+++ b/src/backend/core/api/viewsets.py
@@ -13,9 +13,9 @@ from django.core.exceptions import ValidationError
 from django.core.files.storage import default_storage
 from django.db import models as db
 from django.db.models import (
-    Count,
     Exists,
     F,
+    Func,
     OuterRef,
     Q,
     Subquery,
@@ -353,13 +353,22 @@ class DocumentViewSet(
             return serializers.ListDocumentSerializer
         return self.serializer_class
 
-    def get_queryset(self):
-        """Optimize queryset to include favorite status for the current user."""
-        queryset = super().get_queryset()
+    def annotate_queryset(self, queryset):
+        """Annotate document queryset with favorite and number of accesses."""
         user = self.request.user
 
-        # Annotate the number of accesses associated with each document
-        queryset = queryset.annotate(nb_accesses=Count("accesses", distinct=True))
+        # Annotate the number of accesses taking into account ancestors
+        ancestor_accesses_query = (
+            models.DocumentAccess.objects.filter(
+                document__path=Left(OuterRef("path"), Length("document__path")),
+            )
+            .order_by()
+            .annotate(total_accesses=Func(Value("id"), function="COUNT"))
+            .values("total_accesses")
+        )
+
+        # Annotate with the number of accesses, default to 0 if no accesses exist
+        queryset = queryset.annotate(nb_accesses=Subquery(ancestor_accesses_query))
 
         if not user.is_authenticated:
             # If the user is not authenticated, annotate `is_favorite` as False
@@ -369,19 +378,13 @@ class DocumentViewSet(
         favorite_exists = models.DocumentFavorite.objects.filter(
             document_id=OuterRef("pk"), user=user
         )
-        queryset = queryset.annotate(is_favorite=Exists(favorite_exists))
+        return queryset.annotate(is_favorite=Exists(favorite_exists))
 
-        # Annotate the queryset with the logged-in user roles
-        user_roles_query = (
-            models.DocumentAccess.objects.filter(
-                Q(user=user) | Q(team__in=user.teams),
-                document_id=OuterRef("pk"),
-            )
-            .values("document")
-            .annotate(roles_array=ArrayAgg("role"))
-            .values("roles_array")
-        )
-        return queryset.annotate(user_roles=Subquery(user_roles_query)).distinct()
+    def get_queryset(self):
+        """Optimize queryset to include favorite status for the current user."""
+        queryset = super().get_queryset()
+        queryset = self.annotate_queryset(queryset)
+        return queryset.distinct()
 
     def list(self, request, *args, **kwargs):
         """Restrict resources returned by the list endpoint"""
@@ -504,8 +507,9 @@ class DocumentViewSet(
 
         # Users should not see version history dating from before they gained access to the
         # document. Filter to get the minimum access date for the logged-in user
-        access_queryset = document.accesses.filter(
-            db.Q(user=user) | db.Q(team__in=user.teams)
+        access_queryset = models.DocumentAccess.objects.filter(
+            db.Q(user=user) | db.Q(team__in=user.teams),
+            document__path=Left(Value(document.path), Length("document__path")),
         ).aggregate(min_date=db.Min("created_at"))
 
         # Handle the case where the user has no accesses
@@ -543,10 +547,12 @@ class DocumentViewSet(
         user = request.user
         min_datetime = min(
             access.created_at
-            for access in document.accesses.filter(
+            for access in models.DocumentAccess.objects.filter(
                 db.Q(user=user) | db.Q(team__in=user.teams),
+                document__path=Left(Value(document.path), Length("document__path")),
             )
         )
+
         if response["LastModified"] < min_datetime:
             raise Http404
 
diff --git a/src/backend/core/models.py b/src/backend/core/models.py
index d4319213..2994b804 100644
--- a/src/backend/core/models.py
+++ b/src/backend/core/models.py
@@ -18,6 +18,10 @@ from django.core.files.base import ContentFile
 from django.core.files.storage import default_storage
 from django.core.mail import send_mail
 from django.db import models
+from django.db.models.functions import Left, Length
+from django.http import FileResponse
+from django.template.base import Template as DjangoTemplate
+from django.template.context import Context
 from django.template.loader import render_to_string
 from django.utils import timezone
 from django.utils.functional import cached_property, lazy
@@ -31,23 +35,6 @@ from treebeard.mp_tree import MP_Node
 logger = getLogger(__name__)
 
 
-def get_resource_roles(resource, user):
-    """Compute the roles a user has on a resource."""
-    if not user.is_authenticated:
-        return []
-
-    try:
-        roles = resource.user_roles or []
-    except AttributeError:
-        try:
-            roles = resource.accesses.filter(
-                models.Q(user=user) | models.Q(team__in=user.teams),
-            ).values_list("role", flat=True)
-        except (models.ObjectDoesNotExist, IndexError):
-            roles = []
-    return roles
-
-
 class LinkRoleChoices(models.TextChoices):
     """Defines the possible roles a link can offer on a document."""
 
@@ -539,11 +526,30 @@ class Document(MP_Node, BaseModel):
             Bucket=default_storage.bucket_name, Key=self.file_key, VersionId=version_id
         )
 
+    def get_roles(self, user):
+        """Return the roles a user has on a document."""
+        if not user.is_authenticated:
+            return []
+
+        try:
+            roles = self.user_roles or []
+        except AttributeError:
+            try:
+                roles = DocumentAccess.objects.filter(
+                    models.Q(user=user) | models.Q(team__in=user.teams),
+                    document__path=Left(
+                        models.Value(self.path), Length("document__path")
+                    ),
+                ).values_list("role", flat=True)
+            except (models.ObjectDoesNotExist, IndexError):
+                roles = []
+        return roles
+
     def get_abilities(self, user):
         """
         Compute and return abilities for a given user on the document.
         """
-        roles = set(get_resource_roles(self, user))
+        roles = set(self.get_roles(user))
 
         # Compute version roles before adding link roles because we don't
         # want anonymous users to access versions (we wouldn't know from
@@ -551,11 +557,20 @@ class Document(MP_Node, BaseModel):
         # Anonymous users should also not see document accesses
         has_role = bool(roles)
 
-        # Add role provided by the document link
-        if self.link_reach == LinkReachChoices.PUBLIC or (
-            self.link_reach == LinkReachChoices.AUTHENTICATED and user.is_authenticated
-        ):
-            roles.add(self.link_role)
+        # Add roles provided by the document link, taking into account its ancestors
+        link_reaches = list(self.get_ancestors().values("link_reach", "link_role"))
+        link_reaches.append(
+            {"link_reach": self.link_reach, "link_role": self.link_role}
+        )
+
+        for lr in link_reaches:
+            if lr["link_reach"] == LinkReachChoices.PUBLIC:
+                roles.add(lr["link_role"])
+
+        if user.is_authenticated:
+            for lr in link_reaches:
+                if lr["link_reach"] == LinkReachChoices.AUTHENTICATED:
+                    roles.add(lr["link_role"])
 
         is_owner_or_admin = bool(
             roles.intersection({RoleChoices.OWNER, RoleChoices.ADMIN})
@@ -772,11 +787,27 @@ class Template(BaseModel):
     def __str__(self):
         return self.title
 
+    def get_roles(self, user):
+        """Return the roles a user has on a resource."""
+        if not user.is_authenticated:
+            return []
+
+        try:
+            roles = self.user_roles or []
+        except AttributeError:
+            try:
+                roles = self.accesses.filter(
+                    models.Q(user=user) | models.Q(team__in=user.teams),
+                ).values_list("role", flat=True)
+            except (models.ObjectDoesNotExist, IndexError):
+                roles = []
+        return roles
+
     def get_abilities(self, user):
         """
         Compute and return abilities for a given user on the template.
         """
-        roles = get_resource_roles(self, user)
+        roles = self.get_roles(user)
         is_owner_or_admin = bool(
             set(roles).intersection({RoleChoices.OWNER, RoleChoices.ADMIN})
         )
diff --git a/src/backend/core/tests/documents/test_api_document_versions.py b/src/backend/core/tests/documents/test_api_document_versions.py
index e91012b2..83344259 100644
--- a/src/backend/core/tests/documents/test_api_document_versions.py
+++ b/src/backend/core/tests/documents/test_api_document_versions.py
@@ -185,6 +185,82 @@ def test_api_document_versions_list_authenticated_related_pagination(
     assert content["versions"][0]["version_id"] == all_version_ids[2]
 
 
+@pytest.mark.parametrize("via", VIA)
+def test_api_document_versions_list_authenticated_related_pagination_parent(
+    via, mock_user_teams
+):
+    """
+    When a user gains access to a document's versions via an ancestor, the date of access
+    to the parent should be used to filter versions that were created prior to the
+    user gaining access to the document.
+    """
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    grand_parent = factories.DocumentFactory()
+    parent = factories.DocumentFactory(parent=grand_parent)
+    document = factories.DocumentFactory(parent=parent)
+    for i in range(3):
+        document.content = f"before {i:d}"
+        document.save()
+
+    if via == USER:
+        models.DocumentAccess.objects.create(
+            document=grand_parent,
+            user=user,
+            role=random.choice(models.RoleChoices.choices)[0],
+        )
+    elif via == TEAM:
+        mock_user_teams.return_value = ["lasuite", "unknown"]
+        models.DocumentAccess.objects.create(
+            document=grand_parent,
+            team="lasuite",
+            role=random.choice(models.RoleChoices.choices)[0],
+        )
+
+    for i in range(4):
+        document.content = f"after {i:d}"
+        document.save()
+
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/versions/",
+    )
+
+    content = response.json()
+    assert content["is_truncated"] is False
+    # The current version is not listed
+    assert content["count"] == 3
+    assert content["next_version_id_marker"] == ""
+    all_version_ids = [version["version_id"] for version in content["versions"]]
+
+    # - set page size
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/versions/?page_size=2",
+    )
+
+    content = response.json()
+    assert content["count"] == 2
+    assert content["is_truncated"] is True
+    marker = content["next_version_id_marker"]
+    assert marker == all_version_ids[1]
+    assert [
+        version["version_id"] for version in content["versions"]
+    ] == all_version_ids[:2]
+
+    # - get page 2
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/versions/?page_size=2&version_id={marker:s}",
+    )
+
+    content = response.json()
+    assert content["count"] == 1
+    assert content["is_truncated"] is False
+    assert content["next_version_id_marker"] == ""
+    assert content["versions"][0]["version_id"] == all_version_ids[2]
+
+
 def test_api_document_versions_list_exceeds_max_page_size():
     """Page size should not exceed the limit set on the serializer"""
     user = factories.UserFactory()
@@ -314,6 +390,74 @@ def test_api_document_versions_retrieve_authenticated_related(via, mock_user_tea
     assert response.json()["content"] == "new content 1"
 
 
+@pytest.mark.parametrize("via", VIA)
+def test_api_document_versions_retrieve_authenticated_related_parent(
+    via, mock_user_teams
+):
+    """
+    A user who gains access to a document's versions via one of its ancestors, should be able to
+    retrieve the document versions. The date of access to the parent should be used to filter
+    versions that were created prior to the user gaining access to the document.
+    """
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    grand_parent = factories.DocumentFactory()
+    parent = factories.DocumentFactory(parent=grand_parent)
+    document = factories.DocumentFactory(parent=parent)
+    document.content = "new content"
+    document.save()
+
+    assert len(document.get_versions_slice()["versions"]) == 1
+    version_id = document.get_versions_slice()["versions"][0]["version_id"]
+
+    if via == USER:
+        factories.UserDocumentAccessFactory(document=grand_parent, user=user)
+    elif via == TEAM:
+        mock_user_teams.return_value = ["lasuite", "unknown"]
+        factories.TeamDocumentAccessFactory(document=grand_parent, team="lasuite")
+
+    time.sleep(1)  # minio stores datetimes with the precision of a second
+
+    # Versions created before the document was shared should not be seen by the user
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/versions/{version_id:s}/",
+    )
+
+    assert response.status_code == 404
+
+    # Create a new version should not make it available to the user because
+    # only the current version is available to the user but it is excluded
+    # from the list
+    document.content = "new content 1"
+    document.save()
+
+    assert len(document.get_versions_slice()["versions"]) == 2
+    version_id = document.get_versions_slice()["versions"][0]["version_id"]
+
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/versions/{version_id:s}/",
+    )
+
+    assert response.status_code == 404
+
+    # Adding one more version should make the previous version available to the user
+    document.content = "new content 2"
+    document.save()
+
+    assert len(document.get_versions_slice()["versions"]) == 3
+    version_id = document.get_versions_slice()["versions"][0]["version_id"]
+
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/versions/{version_id:s}/",
+    )
+
+    assert response.status_code == 200
+    assert response.json()["content"] == "new content 1"
+
+
 def test_api_document_versions_create_anonymous():
     """Anonymous users should not be allowed to create document versions."""
     document = factories.DocumentFactory()
diff --git a/src/backend/core/tests/documents/test_api_documents_list.py b/src/backend/core/tests/documents/test_api_documents_list.py
index 93e35237..8549eaf0 100644
--- a/src/backend/core/tests/documents/test_api_documents_list.py
+++ b/src/backend/core/tests/documents/test_api_documents_list.py
@@ -59,8 +59,8 @@ def test_api_documents_list_format():
     assert len(results) == 1
     assert results[0] == {
         "id": str(document.id),
-        "abilities": document.get_abilities(user),
         "content": document.content,
+        "abilities": document.get_abilities(user),
         "created_at": document.created_at.isoformat().replace("+00:00", "Z"),
         "creator": str(document.creator.id),
         "is_favorite": True,
@@ -79,7 +79,6 @@ def test_api_documents_list_authenticated_direct(django_assert_num_queries):
     than restricted.
     """
     user = factories.UserFactory()
-
     client = APIClient()
     client.force_login(user)
 
@@ -110,7 +109,7 @@ def test_api_documents_list_authenticated_direct(django_assert_num_queries):
 
     expected_ids = {str(document1.id), str(document2.id), str(child3_with_access.id)}
 
-    with django_assert_num_queries(3):
+    with django_assert_num_queries(7):
         response = client.get("/api/v1.0/documents/")
 
     assert response.status_code == 200
@@ -145,7 +144,7 @@ def test_api_documents_list_authenticated_via_team(
 
     expected_ids = {str(document.id) for document in documents_team1 + documents_team2}
 
-    with django_assert_num_queries(3):
+    with django_assert_num_queries(8):
         response = client.get("/api/v1.0/documents/")
 
     assert response.status_code == 200
@@ -174,7 +173,7 @@ def test_api_documents_list_authenticated_link_reach_restricted(
     other_document = factories.DocumentFactory(link_reach="public")
     models.LinkTrace.objects.create(document=other_document, user=user)
 
-    with django_assert_num_queries(3):
+    with django_assert_num_queries(4):
         response = client.get(
             "/api/v1.0/documents/",
         )
@@ -221,7 +220,7 @@ def test_api_documents_list_authenticated_link_reach_public_or_authenticated(
 
     expected_ids = {str(document1.id), str(document2.id), str(visible_child.id)}
 
-    with django_assert_num_queries(3):
+    with django_assert_num_queries(7):
         response = client.get(
             "/api/v1.0/documents/",
         )
@@ -315,7 +314,7 @@ def test_api_documents_list_favorites_no_extra_queries(django_assert_num_queries
     factories.DocumentFactory.create_batch(2, users=[user])
 
     url = "/api/v1.0/documents/"
-    with django_assert_num_queries(3):
+    with django_assert_num_queries(8):
         response = client.get(url)
 
     assert response.status_code == 200
@@ -328,7 +327,7 @@ def test_api_documents_list_favorites_no_extra_queries(django_assert_num_queries
     for document in special_documents:
         models.DocumentFavorite.objects.create(document=document, user=user)
 
-    with django_assert_num_queries(3):
+    with django_assert_num_queries(8):
         response = client.get(url)
 
     assert response.status_code == 200
diff --git a/src/backend/core/tests/documents/test_api_documents_retrieve.py b/src/backend/core/tests/documents/test_api_documents_retrieve.py
index 4307ed69..370e30fe 100644
--- a/src/backend/core/tests/documents/test_api_documents_retrieve.py
+++ b/src/backend/core/tests/documents/test_api_documents_retrieve.py
@@ -2,16 +2,17 @@
 Tests for Documents API endpoint in impress's core app: retrieve
 """
 
+import random
+
 import pytest
 from rest_framework.test import APIClient
 
 from core import factories, models
-from core.api import serializers
 
 pytestmark = pytest.mark.django_db
 
 
-def test_api_documents_retrieve_anonymous_public():
+def test_api_documents_retrieve_anonymous_public_standalone():
     """Anonymous users should be allowed to retrieve public documents."""
     document = factories.DocumentFactory(link_reach="public")
 
@@ -52,6 +53,70 @@ def test_api_documents_retrieve_anonymous_public():
     }
 
 
+def test_api_documents_retrieve_anonymous_public_parent():
+    """Anonymous users should be allowed to retrieve a document who has a public ancestor."""
+    grand_parent = factories.DocumentFactory(link_reach="public")
+    parent = factories.DocumentFactory(
+        parent=grand_parent, link_reach=random.choice(["authenticated", "restricted"])
+    )
+    document = factories.DocumentFactory(
+        link_reach=random.choice(["authenticated", "restricted"]), parent=parent
+    )
+
+    response = APIClient().get(f"/api/v1.0/documents/{document.id!s}/")
+
+    assert response.status_code == 200
+    assert response.json() == {
+        "id": str(document.id),
+        "abilities": {
+            "accesses_manage": False,
+            "accesses_view": False,
+            "ai_transform": grand_parent.link_role == "editor",
+            "ai_translate": grand_parent.link_role == "editor",
+            "attachment_upload": grand_parent.link_role == "editor",
+            "collaboration_auth": True,
+            "destroy": False,
+            # Anonymous user can't favorite a document even with read access
+            "favorite": False,
+            "invite_owner": False,
+            "link_configuration": False,
+            "media_auth": True,
+            "partial_update": grand_parent.link_role == "editor",
+            "retrieve": True,
+            "update": grand_parent.link_role == "editor",
+            "versions_destroy": False,
+            "versions_list": False,
+            "versions_retrieve": False,
+        },
+        "content": document.content,
+        "created_at": document.created_at.isoformat().replace("+00:00", "Z"),
+        "creator": str(document.creator.id),
+        "is_favorite": False,
+        "link_reach": document.link_reach,
+        "link_role": document.link_role,
+        "nb_accesses": 0,
+        "title": document.title,
+        "updated_at": document.updated_at.isoformat().replace("+00:00", "Z"),
+    }
+
+
+def test_api_documents_retrieve_anonymous_public_child():
+    """
+    Anonymous users having access to a document should not gain access to a parent document.
+    """
+    document = factories.DocumentFactory(
+        link_reach=random.choice(["authenticated", "restricted"])
+    )
+    factories.DocumentFactory(link_reach="public", parent=document)
+
+    response = APIClient().get(f"/api/v1.0/documents/{document.id!s}/")
+
+    assert response.status_code == 401
+    assert response.json() == {
+        "detail": "Authentication credentials were not provided."
+    }
+
+
 @pytest.mark.parametrize("reach", ["restricted", "authenticated"])
 def test_api_documents_retrieve_anonymous_restricted_or_authenticated(reach):
     """Anonymous users should not be able to retrieve a document that is not public."""
@@ -68,8 +133,8 @@ def test_api_documents_retrieve_anonymous_restricted_or_authenticated(reach):
 @pytest.mark.parametrize("reach", ["public", "authenticated"])
 def test_api_documents_retrieve_authenticated_unrelated_public_or_authenticated(reach):
     """
-    Authenticated users should be able to retrieve a public document to which they are
-    not related.
+    Authenticated users should be able to retrieve a public/authenticated document to
+    which they are not related.
     """
     user = factories.UserFactory()
 
@@ -118,6 +183,78 @@ def test_api_documents_retrieve_authenticated_unrelated_public_or_authenticated(
     )
 
 
+@pytest.mark.parametrize("reach", ["public", "authenticated"])
+def test_api_documents_retrieve_authenticated_public_or_authenticated_parent(reach):
+    """
+    Authenticated users should be allowed to retrieve a document who has a public or
+    authenticated ancestor.
+    """
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    grand_parent = factories.DocumentFactory(link_reach=reach)
+    parent = factories.DocumentFactory(parent=grand_parent, link_reach="restricted")
+    document = factories.DocumentFactory(link_reach="restricted", parent=parent)
+
+    response = client.get(f"/api/v1.0/documents/{document.id!s}/")
+
+    assert response.status_code == 200
+    assert response.json() == {
+        "id": str(document.id),
+        "abilities": {
+            "accesses_manage": False,
+            "accesses_view": False,
+            "ai_transform": grand_parent.link_role == "editor",
+            "ai_translate": grand_parent.link_role == "editor",
+            "attachment_upload": grand_parent.link_role == "editor",
+            "collaboration_auth": True,
+            "destroy": False,
+            "favorite": True,
+            "invite_owner": False,
+            "link_configuration": False,
+            "media_auth": True,
+            "partial_update": grand_parent.link_role == "editor",
+            "retrieve": True,
+            "update": grand_parent.link_role == "editor",
+            "versions_destroy": False,
+            "versions_list": False,
+            "versions_retrieve": False,
+        },
+        "content": document.content,
+        "created_at": document.created_at.isoformat().replace("+00:00", "Z"),
+        "creator": str(document.creator.id),
+        "is_favorite": False,
+        "link_reach": document.link_reach,
+        "link_role": document.link_role,
+        "nb_accesses": 0,
+        "title": document.title,
+        "updated_at": document.updated_at.isoformat().replace("+00:00", "Z"),
+    }
+
+
+@pytest.mark.parametrize("reach", ["public", "authenticated"])
+def test_api_documents_retrieve_authenticated_public_or_authenticated_child(reach):
+    """
+    Authenticated users having access to a document should not gain access to a parent document.
+    """
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    document = factories.DocumentFactory(link_reach="restricted")
+    factories.DocumentFactory(link_reach=reach, parent=document)
+
+    response = client.get(f"/api/v1.0/documents/{document.id!s}/")
+
+    assert response.status_code == 403
+    assert response.json() == {
+        "detail": "You do not have permission to perform this action."
+    }
+
+
 @pytest.mark.parametrize("reach", ["public", "authenticated"])
 def test_api_documents_retrieve_authenticated_trace_twice(reach):
     """
@@ -180,9 +317,7 @@ def test_api_documents_retrieve_authenticated_related_direct():
 
     document = factories.DocumentFactory()
     factories.UserDocumentAccessFactory(document=document, user=user)
-    access2 = factories.UserDocumentAccessFactory(document=document)
-    serializers.UserSerializer(instance=user)
-    serializers.UserSerializer(instance=access2.user)
+    factories.UserDocumentAccessFactory(document=document)
 
     response = client.get(
         f"/api/v1.0/documents/{document.id!s}/",
@@ -203,6 +338,115 @@ def test_api_documents_retrieve_authenticated_related_direct():
     }
 
 
+def test_api_documents_retrieve_authenticated_related_parent():
+    """
+    Authenticated users should be allowed to retrieve a document if they are related
+    to one of its ancestors whatever the role.
+    """
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    grand_parent = factories.DocumentFactory(link_reach="restricted")
+    parent = factories.DocumentFactory(parent=grand_parent, link_reach="restricted")
+    document = factories.DocumentFactory(parent=parent, link_reach="restricted")
+
+    access = factories.UserDocumentAccessFactory(document=grand_parent, user=user)
+    factories.UserDocumentAccessFactory(document=grand_parent)
+
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/",
+    )
+    assert response.status_code == 200
+    assert response.json() == {
+        "id": str(document.id),
+        "abilities": {
+            "accesses_manage": access.role in ["administrator", "owner"],
+            "accesses_view": True,
+            "ai_transform": access.role != "reader",
+            "ai_translate": access.role != "reader",
+            "attachment_upload": access.role != "reader",
+            "collaboration_auth": True,
+            "destroy": access.role == "owner",
+            "favorite": True,
+            "invite_owner": access.role == "owner",
+            "link_configuration": access.role in ["administrator", "owner"],
+            "media_auth": True,
+            "partial_update": access.role != "reader",
+            "retrieve": True,
+            "update": access.role != "reader",
+            "versions_destroy": access.role in ["administrator", "owner"],
+            "versions_list": True,
+            "versions_retrieve": True,
+        },
+        "content": document.content,
+        "creator": str(document.creator.id),
+        "created_at": document.created_at.isoformat().replace("+00:00", "Z"),
+        "is_favorite": False,
+        "link_reach": "restricted",
+        "link_role": document.link_role,
+        "nb_accesses": 2,
+        "title": document.title,
+        "updated_at": document.updated_at.isoformat().replace("+00:00", "Z"),
+    }
+
+
+def test_api_documents_retrieve_authenticated_related_nb_accesses():
+    """Validate computation of number of accesses."""
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    grand_parent = factories.DocumentFactory(link_reach="restricted")
+    parent = factories.DocumentFactory(parent=grand_parent, link_reach="restricted")
+    document = factories.DocumentFactory(parent=parent, link_reach="restricted")
+
+    factories.UserDocumentAccessFactory(document=grand_parent, user=user)
+    factories.UserDocumentAccessFactory(document=parent)
+    factories.UserDocumentAccessFactory(document=document)
+
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/",
+    )
+    assert response.status_code == 200
+    assert response.json()["nb_accesses"] == 3
+
+    factories.UserDocumentAccessFactory(document=grand_parent)
+
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/",
+    )
+    assert response.status_code == 200
+    assert response.json()["nb_accesses"] == 4
+
+
+def test_api_documents_retrieve_authenticated_related_child():
+    """
+    Authenticated users should not be allowed to retrieve a document as a result of being
+    related to one of its children.
+    """
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    document = factories.DocumentFactory(link_reach="restricted")
+    child = factories.DocumentFactory(parent=document)
+
+    factories.UserDocumentAccessFactory(document=child, user=user)
+    factories.UserDocumentAccessFactory(document=document)
+
+    response = client.get(
+        f"/api/v1.0/documents/{document.id!s}/",
+    )
+    assert response.status_code == 403
+    assert response.json() == {
+        "detail": "You do not have permission to perform this action."
+    }
+
+
 def test_api_documents_retrieve_authenticated_related_team_none(mock_user_teams):
     """
     Authenticated users should not be able to retrieve a restricted document related to
diff --git a/src/backend/core/tests/documents/test_api_documents_update.py b/src/backend/core/tests/documents/test_api_documents_update.py
index 3724af38..02b8dcf2 100644
--- a/src/backend/core/tests/documents/test_api_documents_update.py
+++ b/src/backend/core/tests/documents/test_api_documents_update.py
@@ -16,6 +16,7 @@ from core.tests.conftest import TEAM, USER, VIA
 pytestmark = pytest.mark.django_db
 
 
+@pytest.mark.parametrize("via_parent", [True, False])
 @pytest.mark.parametrize(
     "reach, role",
     [
@@ -26,12 +27,18 @@ pytestmark = pytest.mark.django_db
         ("public", "reader"),
     ],
 )
-def test_api_documents_update_anonymous_forbidden(reach, role):
+def test_api_documents_update_anonymous_forbidden(reach, role, via_parent):
     """
     Anonymous users should not be allowed to update a document when link
     configuration does not allow it.
     """
-    document = factories.DocumentFactory(link_reach=reach, link_role=role)
+    if via_parent:
+        grand_parent = factories.DocumentFactory(link_reach=reach, link_role=role)
+        parent = factories.DocumentFactory(parent=grand_parent, link_reach="restricted")
+        document = factories.DocumentFactory(parent=parent, link_reach="restricted")
+    else:
+        document = factories.DocumentFactory(link_reach=reach, link_role=role)
+
     old_document_values = serializers.DocumentSerializer(instance=document).data
 
     new_document_values = serializers.DocumentSerializer(
@@ -52,6 +59,7 @@ def test_api_documents_update_anonymous_forbidden(reach, role):
     assert document_values == old_document_values
 
 
+@pytest.mark.parametrize("via_parent", [True, False])
 @pytest.mark.parametrize(
     "reach,role",
     [
@@ -61,7 +69,9 @@ def test_api_documents_update_anonymous_forbidden(reach, role):
         ("restricted", "editor"),
     ],
 )
-def test_api_documents_update_authenticated_unrelated_forbidden(reach, role):
+def test_api_documents_update_authenticated_unrelated_forbidden(
+    reach, role, via_parent
+):
     """
     Authenticated users should not be allowed to update a document to which
     they are not related if the link configuration does not allow it.
@@ -71,7 +81,12 @@ def test_api_documents_update_authenticated_unrelated_forbidden(reach, role):
     client = APIClient()
     client.force_login(user)
 
-    document = factories.DocumentFactory(link_reach=reach, link_role=role)
+    if via_parent:
+        grand_parent = factories.DocumentFactory(link_reach=reach, link_role=role)
+        parent = factories.DocumentFactory(parent=grand_parent, link_reach="restricted")
+        document = factories.DocumentFactory(parent=parent, link_reach="restricted")
+    else:
+        document = factories.DocumentFactory(link_reach=reach, link_role=role)
 
     old_document_values = serializers.DocumentSerializer(instance=document).data
     new_document_values = serializers.DocumentSerializer(
@@ -93,6 +108,7 @@ def test_api_documents_update_authenticated_unrelated_forbidden(reach, role):
     assert document_values == old_document_values
 
 
+@pytest.mark.parametrize("via_parent", [True, False])
 @pytest.mark.parametrize(
     "is_authenticated,reach,role",
     [
@@ -102,10 +118,10 @@ def test_api_documents_update_authenticated_unrelated_forbidden(reach, role):
     ],
 )
 def test_api_documents_update_anonymous_or_authenticated_unrelated(
-    is_authenticated, reach, role
+    is_authenticated, reach, role, via_parent
 ):
     """
-    Authenticated users should be able to update a document to which
+    Anonymous and authenticated users should be able to update a document to which
     they are not related if the link configuration allows it.
     """
     client = APIClient()
@@ -116,7 +132,12 @@ def test_api_documents_update_anonymous_or_authenticated_unrelated(
     else:
         user = AnonymousUser()
 
-    document = factories.DocumentFactory(link_reach=reach, link_role=role)
+    if via_parent:
+        grand_parent = factories.DocumentFactory(link_reach=reach, link_role=role)
+        parent = factories.DocumentFactory(parent=grand_parent, link_reach="restricted")
+        document = factories.DocumentFactory(parent=parent, link_reach="restricted")
+    else:
+        document = factories.DocumentFactory(link_reach=reach, link_role=role)
 
     old_document_values = serializers.DocumentSerializer(instance=document).data
     new_document_values = serializers.DocumentSerializer(
@@ -147,24 +168,34 @@ def test_api_documents_update_anonymous_or_authenticated_unrelated(
             assert value == new_document_values[key]
 
 
+@pytest.mark.parametrize("via_parent", [True, False])
 @pytest.mark.parametrize("via", VIA)
-def test_api_documents_update_authenticated_reader(via, mock_user_teams):
+def test_api_documents_update_authenticated_reader(via, via_parent, mock_user_teams):
     """
-    Users who are reader of a document but not administrators should
-    not be allowed to update it.
+    Users who are reader of a document should not be allowed to update it.
     """
     user = factories.UserFactory(with_owned_document=True)
 
     client = APIClient()
     client.force_login(user)
 
-    document = factories.DocumentFactory(link_role="reader")
+    if via_parent:
+        grand_parent = factories.DocumentFactory(link_reach="restricted")
+        parent = factories.DocumentFactory(parent=grand_parent, link_reach="restricted")
+        document = factories.DocumentFactory(parent=parent, link_reach="restricted")
+        access_document = grand_parent
+    else:
+        document = factories.DocumentFactory(link_reach="restricted")
+        access_document = document
+
     if via == USER:
-        factories.UserDocumentAccessFactory(document=document, user=user, role="reader")
+        factories.UserDocumentAccessFactory(
+            document=access_document, user=user, role="reader"
+        )
     elif via == TEAM:
         mock_user_teams.return_value = ["lasuite", "unknown"]
         factories.TeamDocumentAccessFactory(
-            document=document, team="lasuite", role="reader"
+            document=access_document, team="lasuite", role="reader"
         )
 
     old_document_values = serializers.DocumentSerializer(instance=document).data
@@ -188,10 +219,11 @@ def test_api_documents_update_authenticated_reader(via, mock_user_teams):
     assert document_values == old_document_values
 
 
+@pytest.mark.parametrize("via_parent", [True, False])
 @pytest.mark.parametrize("role", ["editor", "administrator", "owner"])
 @pytest.mark.parametrize("via", VIA)
 def test_api_documents_update_authenticated_editor_administrator_or_owner(
-    via, role, mock_user_teams
+    via, role, via_parent, mock_user_teams
 ):
     """A user who is editor, administrator or owner of a document should be allowed to update it."""
     user = factories.UserFactory(with_owned_document=True)
@@ -199,13 +231,23 @@ def test_api_documents_update_authenticated_editor_administrator_or_owner(
     client = APIClient()
     client.force_login(user)
 
-    document = factories.DocumentFactory()
+    if via_parent:
+        grand_parent = factories.DocumentFactory(link_reach="restricted")
+        parent = factories.DocumentFactory(parent=grand_parent, link_reach="restricted")
+        document = factories.DocumentFactory(parent=parent, link_reach="restricted")
+        access_document = grand_parent
+    else:
+        document = factories.DocumentFactory(link_reach="restricted")
+        access_document = document
+
     if via == USER:
-        factories.UserDocumentAccessFactory(document=document, user=user, role=role)
+        factories.UserDocumentAccessFactory(
+            document=access_document, user=user, role=role
+        )
     elif via == TEAM:
         mock_user_teams.return_value = ["lasuite", "unknown"]
         factories.TeamDocumentAccessFactory(
-            document=document, team="lasuite", role=role
+            document=access_document, team="lasuite", role=role
         )
 
     old_document_values = serializers.DocumentSerializer(instance=document).data
@@ -238,52 +280,6 @@ def test_api_documents_update_authenticated_editor_administrator_or_owner(
             assert value == new_document_values[key]
 
 
-@pytest.mark.parametrize("via", VIA)
-def test_api_documents_update_authenticated_owners(via, mock_user_teams):
-    """Administrators of a document should be allowed to update it."""
-    user = factories.UserFactory(with_owned_document=True)
-
-    client = APIClient()
-    client.force_login(user)
-
-    document = factories.DocumentFactory()
-    if via == USER:
-        factories.UserDocumentAccessFactory(document=document, user=user, role="owner")
-    elif via == TEAM:
-        mock_user_teams.return_value = ["lasuite", "unknown"]
-        factories.TeamDocumentAccessFactory(
-            document=document, team="lasuite", role="owner"
-        )
-
-    old_document_values = serializers.DocumentSerializer(instance=document).data
-
-    new_document_values = serializers.DocumentSerializer(
-        instance=factories.DocumentFactory()
-    ).data
-
-    response = client.put(
-        f"/api/v1.0/documents/{document.id!s}/", new_document_values, format="json"
-    )
-
-    assert response.status_code == 200
-    document = models.Document.objects.get(pk=document.pk)
-    document_values = serializers.DocumentSerializer(instance=document).data
-    for key, value in document_values.items():
-        if key in [
-            "id",
-            "created_at",
-            "creator",
-            "link_reach",
-            "link_role",
-            "nb_accesses",
-        ]:
-            assert value == old_document_values[key]
-        elif key == "updated_at":
-            assert value > old_document_values[key]
-        else:
-            assert value == new_document_values[key]
-
-
 @pytest.mark.parametrize("via", VIA)
 def test_api_documents_update_administrator_or_owner_of_another(via, mock_user_teams):
     """