The man at the centre of a surrogacy scandal involving a disabled baby allegedly left in Thailand by his Australian parents reportedly has a prior conviction for indecent assault and has spent time in jail.

The biological parents of seven-month-old Gammy are accused of abandoning him in Thailand after he and his healthy twin sister were born to a local surrogate.

His sister was brought back to Australia.

The Nine Network says the father's wife has confirmed her husband has a conviction for indecently dealing with a child under 13 and has served jail time after being found guilty in 1998.


She says she is aware of the past conviction, Nine says, but believes he is a good man despite his criminal records.

The couple, who have not been identified but live in Western Australia, deny abandoning Gammy and claim they had no knowledge of a second child.

Meanwhile, Gammy's surrogate mother says she is shocked by the reports regarding his father and now wants the boy's sister returned to her in Thailand, Fairfax reports.