Lidia’s answer: 23 Pa. Cons. Stat. § 2511(a) provides: § 2511. Grounds for involuntary termination.
(a) General rule.–The rights of a parent in regard to a
child may be terminated after a petition filed on any of the
following grounds:
(1) The parent by conduct continuing for a period of at
least six months immediately preceding the filing of the
petition either has evidenced a settled purpose of
relinquishing parental claim to a child or has refused or
failed to perform parental duties.
Moreover, him moving to another state does not absolve him of paying child support. You can get a judgment in PA and transfer it to another state for enforcement. You should consult the interstate unit in the Domestic Relations in your county