A campaign for a baby with Down syndrome abandoned to his surrogate mother has already raised over $120,000.

The baby boy, named Gammy, also suffers from a congenital heart condition and needs crucial medical attention that his surrogate mother cannot afford to pay, the BBC reported.

Pattaramon Chanbua was paid $15,000 to be a surrogate for an unidentified set of Australian parents. Four months after she became pregnant the baby's condition was revealed; the parents asked her to get an abortion, but Chanbua refused on the grounds of her Buddhist beliefs. The parents took Gammy's twin sister but left the baby boy behind.

The 21-year-old surrogate already has two children, and cannot afford to pay for Gammy's expensive medical needs.

"Because of the poverty and debts and the money that was offered was a lot for me. In my mind, with that money we can educate our children and repay our debt," Chanbua told ABC Australia.

Despite these hardships Chanbua still cares for Gammy the best she can.

"Why does he have to be abandoned while the other baby has it easy?" she asked. "I feel sorry for him. I don't know what to do. I chose to have him, not to hurt him. I love him. He was in my tummy for nine months, it's like my child."

Gammy now has a GoFundMe online campaign that has been hit with overwhelming responses. Hundreds of generous individuals have donated towards the $150,000 target. Many messages of the site also showed support for baby boy, the BBC reported.

"May this selfish and heartless couple be exposed and shamed for this horrible neglect!" one comment read, the BBC reported.

Thai health official Tares Krassanairawiwong told the BBC it is illegal to pay for surrogacy in Thailand.

"Surrogacy can be done in Thailand but it has to comply with the laws. A surrogate has to be related to the intended parents and no money can be involved," he said.

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