diff --git a/storyboardclient/v1/timeline.py b/storyboardclient/v1/timeline.py
index 57c99c1..d8b6376 100644
--- a/storyboardclient/v1/timeline.py
+++ b/storyboardclient/v1/timeline.py
@@ -19,6 +19,7 @@ from storyboardclient import base
 class Comment(base.BaseObject):
     content = None
     is_active = None
+    in_reply_to = None
 
 
 class TimeLineEvent(base.BaseObject):
@@ -38,4 +39,4 @@ class CommentsNestedManager(base.BaseNestedManager):
 class TimeLineEventsNestedManager(base.BaseNestedManager):
     parent_url_key = "stories"
     url_key = "events"
-    resource_class = TimeLineEvent
\ No newline at end of file
+    resource_class = TimeLineEvent