The American-Spanish gay couple fighting for custody of their seven-month-old surrogate daughter Carmen have claimed on their Facebook page that they have met the egg donor who wants Carmen to stay with them.
Gordon Lake and his partner Manuel Santos Valero, who are living in Bangkok, wrote on their Facebook page "Bringcarmenhome" that they had contacted the "beautiful person" who donated the egg that allowed them to have their "little princess", Carmen.
"The woman is so nice and sweet and they resemble each other," the couple wrote on their page. "She is a good woman who wants the best future for Carmen and she knows Carmen should be with the family that wants her so badly. So the egg donor has agreed to help us by taking a DNA test. And the result is 99.9%."
The couple did not disclose the identity of the woman, or say where the DNA test had been conducted.
The DNA test results have given the couple hope that they will be able to take Carmen back to the United States, said Surapong Kongchantuk, chairman of the Lawyers Council of Thailand's human rights subcommittee on ethnic minorities, the stateless, migrant workers and the displaced.
Mr Lake and Mr Valero are embroiled in a dispute with the surrogate mother they paid to give birth to Carmen, who is refusing to sign over custody of the child despite having no biological ties to her.
Carmen was born before the new surrogacy law, which could have improved their chances.
Their case must be judged under the old law, which automatically grants custody of a child to the birth mother.
The new surrogacy law, by contrast, says custody of the child will be given to the owner of the sperm and the egg donor.
Mr Surapong said the case must be considered under the previous law. But he still sees hope for the couple despite the legal technicalities.
"The rights to the child may switch to the father if he can prove that the mother is by no means genetically related to the child, such as proving the egg does not belong to the surrogate [birth] mother," Mr Surapong said.
Last week, more than 100 activists supporting the couple submitted a request to the Social Development and Human Security Ministry to look into the case and speed up negotiations between the surrogate mother and the American-Spanish couple.
Many believe the surrogate mother's refusal to hand over custody of Carmen to Mr Gordon and his partner stems from the fact they are a gay couple.
This has led to an increase in support from LGBT networks and other groups working with gender diversity in Thailand.
The National Human Rights Commission is also helping the couple with their case.