The father can live with whomever he chooses. Since only HIS income can be used to determine support, whether you live with him or not doesn't factor into the support amount. The support is determined by a computer program so if the info entered into the program is correct, then that is the child support he needs to pay. What I find disturbing is that he cannot see his children. Unless it is shown he an addict or abusive, he has a right and responsibility to see his kids. The court will not look kindly on a mother who, out of spite, is keeping a father from his children. He in entitled to be with his kids UNLESS he is a bad father. But that means he is abusive or an addict. That he lives with you does not matter, unless you were an addict or abusive. The only other reason would be where you live is unfit for children to be there and puts them in danger. Only you can answer these questions. The court could give the mother attorney's fees IF she proved he was a bad father. But since, according to you, he can't see them, why would the mother be taking him back to court? IMO, I don't see how you living there matters at all.