diff --git a/boards/models/post/__init__.py b/boards/models/post/__init__.py
--- a/boards/models/post/__init__.py
+++ b/boards/models/post/__init__.py
@@ -347,10 +347,12 @@ def connect_replies(instance, **kwargs):
         try:
             referenced_post = Post.objects.get(id=post_id)
 
-            referenced_post.referenced_posts.add(instance)
-            referenced_post.last_edit_time = instance.pub_time
-            referenced_post.build_refmap()
-            referenced_post.save(update_fields=['refmap', 'last_edit_time'])
+            # Connect only to posts that are not connected to already
+            if not referenced_post.referenced_posts.filter(id=instance.id).exists():
+                referenced_post.referenced_posts.add(instance)
+                referenced_post.last_edit_time = instance.pub_time
+                referenced_post.build_refmap()
+                referenced_post.save(update_fields=['refmap', 'last_edit_time'])
         except ObjectDoesNotExist:
             pass