Thousands of dollars have been raised for a six-month-old baby, known as Gammy, who was left with his surrogate after his Australian parents discovered he had Down syndrome and a congenital heart condition.
The parents took his twin sister back to Australia but left Gammy with his Thai surrogate who cannot afford the child's medical costs.
After the boy's plight was revealed, a "Hope for Gammy" campaign to help pay for his medical treatment was set up, with over $135,000 (£74,000) raised so far.
Financially-stricken Pattharamon Janbua, 21, was offered $11,700 to be a surrogate mother for the Australian couple, and later promised $1,673 to have the second baby.
But during routine checks four months into the pregnancy, doctors revealed that one of the babies had Down syndrome.
The Australian parents reportedly told Pattharamon to have an abortion as they did not want the child, but she refused, the Sydney Morning Herald reported.
The couple refused to take the twins, and instead took the baby girl back to Australia, leaving Gammy behind.
"I know he isn't genetically connected to me but I carried him for nine months. Every time I look at him I feel sorry and guilty," Pattharamon said.
More than 3,000 donations have now been made to the "Hope for Gammy" campaign, with many revealing their shock over the situation.
The generous donations included Bangkok-based fertility doctor Dr Pisit Tantiwattanakul who donated $3,000 to the cause.
Many expressed outrage over the parent's actions, and questioned how they would explain the situation to Gammy's twin sister.
"What are the parents going to explain to their 'healthy' child about abandoning her 'unhealthy' twin brother? What a disgrace these parents are (if you can call them parents)," one person wrote on the page.
"As a step-father to a wonderful 14-year-old boy with Down Syndrome I think it's disgusting that the Aussie parents would do such a thing. Hopefully the money raised will help his mother. Great cause!" another said.
The fundraisers said a trust fund with two well-known Thai charities was being established to ensure all of the money raised is used only for the care of Gammy and his family.
Following her experience, Ms Pattharamon warned other women not to get involved in surrogacy arrangements.
“I would like to tell Thai women don’t get into this business as a surrogate. Don’t just think only for money, if something goes wrong no one will help us and the baby will be abandoned from society, then we have to take responsibility for that.”