diff --git a/boards/models/tag.py b/boards/models/tag.py
--- a/boards/models/tag.py
+++ b/boards/models/tag.py
@@ -146,5 +146,5 @@ class Tag(models.Model, Viewable):
 
     def get_images(self):
         return Attachment.objects.filter(
-            post_attachments__thread__tags__in=[self]).filter(
-            mimetype__in=FILE_TYPES_IMAGE).order_by('-post_images__pub_time')
\ No newline at end of file
+            attachment_posts__thread__tags__in=[self]).filter(
+            mimetype__in=FILE_TYPES_IMAGE).order_by('-attachment_posts__pub_time')
\ No newline at end of file
diff --git a/boards/models/thread.py b/boards/models/thread.py
--- a/boards/models/thread.py
+++ b/boards/models/thread.py
@@ -142,7 +142,7 @@ class Thread(models.Model):
         return self.get_replies().filter(
             attachments__mimetype__in=FILE_TYPES_IMAGE)\
             .annotate(images_count=Count(
-            'attachments')).aggregate(Sum('images_count'))['images_count__sum']
+            'attachments')).aggregate(Sum('images_count'))['images_count__sum'] or 0
 
     def can_bump(self) -> bool:
         """