diff --git a/aleksis/apps/chronos/managers.py b/aleksis/apps/chronos/managers.py
index f02daf466b083e10b7af26dc77df8a0f3042b33c..4cf0cfe6f2f91d999aee35ecacff32f5669cf356 100644
--- a/aleksis/apps/chronos/managers.py
+++ b/aleksis/apps/chronos/managers.py
@@ -100,10 +100,15 @@ class LessonEventQuerySet(RecurrencePolymorphicQuerySet):
         """Get all lesson events for a certain person (as teacher/participant, including amends)."""
         from .models import LessonEvent
 
-        amended = LessonEvent.objects.filter(
-            Q(amended_by__isnull=False) & (Q(teachers=person) | Q(groups__members=person))
-        ).values_list("amended_by__pk", flat=True)
-        return Q(teachers=person) | Q(groups__members=person) | Q(pk__in=amended)
+        amended = (
+            LessonEvent.objects.filter(
+                Q(amended_by__isnull=False) & (Q(teachers=person) | Q(groups__members=person))
+            )
+            .values_list("amended_by__pk", flat=True)
+            .union(LessonEvent.objects.filter(teachers=person).values_list("pk", flat=True))
+            .union(LessonEvent.objects.filter(groups__members=person).values_list("pk", flat=True))
+        )
+        return Q(pk__in=amended)
 
     def for_person(self, person: Union[int, Person]) -> "LessonEventQuerySet":
         """Get all lesson events for a certain person (as teacher/participant, including amends)."""