So, this is a good time for direct guidance. You can tell him and he is old enough to listen about what he can and can't do. Grabbing someone's chest? Not okay. Breast fed or not, not okay. That is not respecting people's body boundaries. So, teach him body boundaries. This is private parts, breasts, nipples of anyone, etc. You can ask him NOT to do what he is doing to your stomach. It's reasonable. :>) Cuddle with him in other ways. He's certainly struggling with some changes due to the separation but just guide him with what he can and can't do. If he will not listen, write us back!