“My father never paid child support for me or my brother. We are both adults now and wonder if he can be sued?”
If there was an order to pay support that he simply did not follow, then the back support could be sought. It would be enforceable in the same court that initially made child support orders. If there never was an order for support, then you’re probably not going to have any success getting money from your father for the support he never gave you.