diff --git a/biscuit/apps/alsijil/views.py b/biscuit/apps/alsijil/views.py
index bea753276aa3130eafffe7aeb28f08ad816bb312..82dc8ea57008e13e2459924963199b1087d84caf 100644
--- a/biscuit/apps/alsijil/views.py
+++ b/biscuit/apps/alsijil/views.py
@@ -122,7 +122,7 @@ def week_view(request: HttpRequest, year: Optional[int] = None, week: Optional[i
         persons = Person.objects.filter(
             is_active=True
         ).filter(
-            Q(member_of=group) | Q(member_of__parent_groups=group)
+            member_of__lessons__periods__in=lesson_periods
         ).distinct().prefetch_related(
             'personal_notes'
         ).annotate(