I met a farang this morning while having breakfast this morning. During the conversation he tells me that he has Thai citizenship because he was adopted by a Thai lady. He is 36 years old and claims to have been adopted by his girlfriend's grandmother who is 60.
He produced a Thai id and house registration.
The guy said that the adopting parent has to be at least 15 years older than you and it got him citizenship in about a year.
Possible? Or not.......