The West Australian couple at the centre of the baby Gammy surrogacy issue has accused his Thai surrogate mother of lying about the circumstances of his birth.

The Bunbury couple initially denied any knowledge of the baby's existence but now say they were told Gammy had only a day to live when he was first born.

The couple, who WAtoday.com.au has decided not to name, said they had been traumatised by a messy legal battle and heavy media attention which had portrayed them as "heartless".

In a statement to Fairfax Media through a family friend, the couple said allegations they abandoned baby Gammy, made by Thai surrogate mother Pattharamon Janbua, were lies.

“This has been absolutely terrifying for them, they are on the edge,” the family friend said.

“Legally they have been told not to say anything but they wouldn’t be able to anyway.”

The family friend said reports the couple had requested an abortion when they found out Gammy had Down syndrome, and that they had abandoned the baby boy, were completely false.

The birth of the twins had been planned to take place at a major international hospital in Thailand.

But surrogate mother Pattaramon Janbua  had gone to a smaller hospital, which made the surrogacy agreement void, according to the couple.

This meant the couple had no legal rights to the babies, even though they are the biological parents.

The babies were born two months premature due to medical complications.

She said the couple were not told that Gammy had Down syndrome. But they were told he had a congenital heart condition.

“Gammy was very sick when he was born and the biological parents were told he would not survive and he had a day, at best, to live and to say goodbye,” she said.

The surrogate mother then said she wanted to keep Gammy and give him a proper Thai funeral.

The couple became embroiled in a legal battle to bring home the female twin. Ms Janbua, 21, finally agreed to hand the baby girl over, but the couple was terrified she could change her mind.

“All this happened when Thailand was in a military lockdown and very difficult to get around,” the friend said.

“The biological parents were heartbroken that they couldn’t take their boy with them and never wanted to give him up, but to stay would risk them losing their daughter also.

“They prayed for Gammy to survive but were told by doctors that he was too sick, not because of the Down syndrome but because of his heart and lung conditions and infection.”

The couple spent two months in Thailand and extended their visas but due to military unrest they had no option but to leave without Gammy.

Claims from the surrogate mother that the couple had “ignored” Gammy when they visited the hospital are completely untrue, according to the friend.

She said they were not allowed to touch or hold either of the twins.

The couple had bought baby items for both babies, not just the little girl.

Media outlets have been camped outside the parents’ South Bunbury home since early Monday morning.

- with the Bunbury Mail