Whoa! Wait a minute here!!! I DO stop it and would never ignore my child being hurt and not step in.
I didn't get that from your post and misinterpreted what was happening. I apologize.
H
Allowing this child to come into your home again is allowing another child to abuse your child - yet again.
Rethink your priorities here!
This kind of behavior is teaching your child that it is okay to abuse him. It is repeatedly sending him the message that he does not deserve better...