At 13, he was a precocious boy who impressed with his thirst for knowledge and eloquence.
But as he grew older, something changed in Amos Yee, who's now 16.
"The boy I knew back then was very different from the boy now," said a former member of a writing club who wanted to be known only as Mr Yap.
He and Amos were in the writing club in 2011.
Mr Yap wants to remain anonymous because he does not want to be linked to Amos, who has got into trouble over a video posted on his YouTube channel last Friday.
The eight-minute video, which features him ranting against the late Mr Lee Kuan Yew and Christians, has since been taken down.
The police said in a statement late last night that a 16-year-old boy was arrested on Sunday in relation to the video.
They said they had received more than 20 reports from Friday to Sunday about the video that contained, in part, insensitive and disparaging remarks against Christians.
The statement said the teen will be charged with these offences today:
- Deliberate intention of wounding the religious or racial feelings of any person, for which he can be jailed up to three years, fined, or both.
- Circulating obscene material, for which he can be jailed up to three months, fined, or both.
- Making threatening, abusive or insulting communication, which is heard, seen or otherwise perceived by any person likely to be caused harassment, alarm or distress, for which he can be fined up to $5,000.
Deputy Commissioner of Police (Investigations & Intelligence) Tan Chye Hee said: "Police take a stern view of acts that could threaten religious harmony in Singapore.
"Any person who uploads offensive content online with deliberate intention of wounding the religious or racial feelings of any person will be firmly dealt with in accordance with the law."
In 2012, Amos enraged netizens with his satirical take on Chinese New Year, saying it copies "American New Year".
The New Paper understands that the obscene charge is related to what he posted on his blog.
Mr Yap told TNP about his impression of Amos when he was 13: "He was very polite and nice. He sounded confident, well-spoken and articulate while his peers were kind of quiet and shy.
"You would think he had something going for himself. He was reading stuff that people weren't reading at his age and always asking questions."
But in recent years, Amos started putting everyone down.
"Amos became so negative. He used to be opinionated but now he's rude to everyone around him," Mr Yap said.
"We all felt he had potential but seeing how he's shooting his mouth off, being offensive and using his brilliance for this... As a writer, you have many ways to air your opinions, and this isn't what we taught him."
Mr Yap added that the writing club members began dissociating themselves from Amos as any link to him was deemed "embarrassing".
Radio DJ and TNP entertainment columnist Jason Johnson was also shocked and heartbroken to see this different side of Amos.
They had met in 2012 for the second edition of TNP's FiRST Film Fest. Amos, who had won awards at the inaugural event in 2011, was one of the award presenters.
Mr Johnson, who has not seen Amos' video but read reports about it, said: "I always thought he was a sweet kid. He was very respectful to me, pleasant and funny.
"He was a nice and shy kid. He's talented and smart. I thought he had a lot of potential.
"I was kind of heartbroken. How can he be so stupid?
"I knew the kid back when he was 14 and I had a lot of fondness for him. I wish he would stick to the arts and movies, and not wade into these areas."
While he understood why people would be furious, he pointed out that Amos is "still a kid".
"I hope this doesn't become the thing that defines his life. There are already very serious consequences. I just hope that it's something that he can learn from," said the father-of-two.
"There's a way to say things without upsetting people - that's what he's got to learn."