These issues should have been resolved before he moved in. It's a lot harder now to get him out.
The woman was really taking chances with her children by allowing a guy to move into their home without having established house rules with him. It sounds like they didn't even have good communication or understanding of each other the begin with. It's almost like she allowed a stranger into the home.
The news is full of stories about live-in boyfriends (especially ones who aren't the children's fathers) who abuse and kill the kids. It's a risky scenario.