Child support from a US resident

[OzMan]

A lady I know had a 10 year relationship with a US citizen while he lived in BKK. There was a child by the relationship who has a US passport and birth certificate since the father acknowledged paternity. The father returned to the US (Texas) and voluntarily paid child support until 18 months ago. He no no longer pays child support and all efforts to contact him have failed. Has anybody any experience of getting a US resident to pay child support through state authorities?

[scorecard]

Has there been any conclusive check that he is still alive?

[OzMan]

The lady is in email contact with his older daughter who she seems to be on good terms with. She says that she too does not know where he lives. The older daughter has not mentioned that he has died.