None of my children are 18. I had a "Darwin" argument over a medical bill for the baby she had with her new spouse, that some how I am responsible for? Even the CA agreed "Your ex wife had another persons child, the child is not yours and you have to pay for it...........we'll delete that today"

But I did live in LA, but good/bad news, once he turns 18 you may not be responsible for the debt acquired for the same year he turned 18.