I was divorced and in my order he had to pay me child support and a year after she went to live with him and know she's three months from being 18 and he wants me to pay him for the last two years she's has lived with him. He never paid me for the two years she lived with me and I have a court order he does not have one. Any advice would be helpful and this took place in Washington state.

If he failed to file when she moved in with him its unlikely he will be awarded back support. He will need to file to get anything.

If he failed to file when she moved in with him its unlikely he will be awarded back support. He will need to file to get anything.

And, of course, if he does file, OP should plead as a setoff what he owes her.