my parenting layers adobe animate has gap in between key frames

https://documentcloud.adobe.com/link/track?uri=urn:aaid:scds:US:27cf3e2f-4e3f-4fff-b2d3-988eb6d4f318 

I put the parenting option in my rig in adobe animate 2020  and i notice when i adjust the charactor to create my walking cycle the rig distorts  in between the  key frames . my quetsion is there a way to fix this. I thought the parenting tool prevented the rig from being distorted  is there a trick to fix the broken rig example in image in between the key frames the classic tween, the robot leg breaks in the bottom portion  even though my parenting option is on. is there a video that teaches how to rig character correctly so that when you parent it and use classic tween the rig stays intact as it moves.

https://documentcloud.adobe.com/link/track?uri=urn:aaid:scds:US:27cf3e2f-4e3f-4fff-b2d3-988eb6d4f318