A.B.
It seems like you haven't "gotten over it" if your son is telling other people his last name is different from what it is and you are allowing it. 4 year olds don't make those kinds of decisions on your own. It seems like you are the one that may be encouraging the problems you are talking about. You need to be the grown up here and encourage your son to spend time with his dad and be proud of the last name that he shares with him. Kids learn by example. You said yourself that he pays his child support and wants and does spend time with your son. Why aren't you encouraging your son? There are lots of moms out there who do it all on there own. Your reward should be in raising a happy, healthy kid that knows BOTH his parents are involved in his life.