If my fiancé's ex goes to court and changes his son's last name to one other than his is he obligated to pay child support?

Hello finit:

His name didn't make him the father - his tallywacker did. He can change his or his sons name all he wants, but he can't change his tallywacker.

Yes, he's obligated.

excon

LOL! Excon, you cracked me up with that one!
Your fiancé is required by law to pay child support until the child reaches maturity. Unless, his obligation is forgiven by the custodial parent.

He can if he wishes challenge in court their right to change the child's last name, since they can not without his approval if he is listed on the birth certificate and the child has his last name. ( and any change in many places) so if he does not like the child's name being changed, he may file a motion in court to have that over turned.

Yes he will have to pay child support ( which he should want to of course since it is his child and his moral obligation to do so) following the written child support decree.

If he is proven to be the father, then yes. The name means nothing as far as determining legal paternity and the accompanying obligations.