His adoptive maternal grandmother had bought him from his birth mum for 2,000 ringgit (S$700 now).
MediaCorp actor Chen Hanwei found out the harsh truth about his birth only three years ago, when he turned 40.
And it was only this week that he finally opened up about it.
At a press conference for his first movie, Ghost Child, on Monday, the veteran Malaysian-born actor recounted how he had his first ghostly encounter on the set of The Village Hero back in 1990.
But during the filming of the then-SBC (Singapore Broadcasting Corporation) period drama, something else had traumatised him more.
He had received a call from an unidentified old woman who told him that the couple he thought were his parents - a 74-year-old teacher and a 73-year-old housewife from Johor Baru - were not his biological parents.
But not wanting to rock the boat, he kept that knowledge to himself for 20 years. Three years ago, he finally asked his parents for the truth.
Chen, 43, told The New Paper: "I felt that since they were growing old, I wanted to know what happened back then.
"Twenty years ago, I had asked my dad and mum separately where I was born and my dad said 'house' while my mum said 'hospital', so I already knew that something didn't add up.
"I kept this with me all this time, but I'm glad my mum, who cried because she thought I would give them up when I found out, (eventually) told me the whole story.
"I love my mum so much; of course, I would never do that."
He added that after being contacted by the mysterious caller, he was initially very sad - not because he suspected he was adopted but because his parents had not dare to tell him about it.
His sister, a pharmacy manager in Malaysia who is three years older, is also adopted but from a different birth mum. Chen said that after his mother had adopted him and his sister, she suffered a miscarriage.
Three years ago, when confronted by him, she broke down and told him that his birth mother had him so she could sell him to earn money.
Said Chen: "Adoptions were all the rage back then, some of my cousins are also adopted.
"My mum could conceive but she was initially afraid of the pain of childbirth.
"At that time, 2,000 ringgit was a lot. I don't know who my biological parents are and I don't wish to find out."
He added that he had come from an impoverished background and that his family became so poor - especially after the extra expenses incurred by both children - that they couldn't afford to buy him toys.
A cup of ice lemon tea was considered a luxury and he said that the family of four would share one cup of the drink once a year.
Though they had to move from one relative's house to another because they couldn't afford their own house, Chen said his family stayed together as they had strong ties.
Now that he has earned his money, he has bought his parents a house and a car.
Often, he also pays for holidays for the entire family. Chen has taken his parents to Hong Kong, Thailand, China and Vietnam and he's looking forward to taking them to South Korea and Taiwan next year.
Said Chen: "I think the woman who called me back in 1990 wanted to create trouble.
"I want to thank her instead as she has brought our family even closer together.
"My parents taught me good manners, to be disciplined and to be clean.
"As I am proud to have them as my parents, I think they are also proud to have me for a son."
In Ghost Child, which is expected to hit cinemas next year, Chen plays a contractor who has to deal with spooky encounters.
On his own encounter, he said: "Back when I was filming The Village Hero, I was sleeping during a break on set and when I woke, I saw a female ghost glide past me and say 'I want...'.
"I was very scared and my friend asked me to see a holy man. So I did and he advised me to go back to the scene of the sighting and to pray.
"I've now got over my fear of ghosts."
The misty-eyed acting veteran added: "I've also come to terms with my adoption.
"I love my parents very much and what I told them was even in my next life, I would still want them to be my parents."
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