diff --git a/server/book/schema/mutations.py b/server/book/schema/mutations.py
index b53e0849..7d20ff46 100644
--- a/server/book/schema/mutations.py
+++ b/server/book/schema/mutations.py
@@ -113,8 +113,12 @@ class AddContentBlock(relay.ClientIDMutation):
 
         if parent is not None:
             parent_chapter = get_object(Chapter, parent).specific
-            parent_chapter.add_child(instance=new_content_block)
-        if after is not None:
+            first_sibling = parent_chapter.get_first_child()
+            if first_sibling is not None:
+                first_sibling.add_sibling(instance=new_content_block, pos='left')
+            else:
+                parent_chapter.add_child(instance=new_content_block)
+        elif after is not None:
             sibling = get_object(ContentBlock, after).specific
             sibling.add_sibling(instance=new_content_block, pos='right')