In 2004, when housewife Ng Saw Yong's son told her he was going to be interviewed, she thought he had got into trouble again.
Pan Wei Hao was then a student in Queensway Secondary School, but had spent time in the Singapore Boys' Home, a juvenile home, after committing a string of offences, including housebreaking.
But he overcame the odds to top the N-level exams in Singapore.
"When I told her about the reporter's visit, she got a shock and asked, 'What have you done wrong again?'" he recalled.
Madam Ng, now 66, said in Mandarin: "He said he was No. 1.
"I told him, 'But you are always top (in school tests).' He said this was different, it was across the nation."
This year, the 29-year-old is the subject of interviews for another reason his mother can be proud of.
He now holds the rank of captain with the Republic of Singapore Air Force. His story was featured last month on the Ministry of Social and Family Development's MSF Conversations blog.
Last year, he was also featured on the Facebook page of Defence Minister Ng Eng Hen, who wrote: "Having tasted life's bitter lessons and given many chances to succeed, Wei Hao will make a good mentor for younger national servicemen."
After his N levels, he was one of the top 10 Secondary 5 students in the O-level examinations in 2005 and won the Lee Kuan Yew Award for Outstanding Normal Course Student that year.
He made it to the Director's List at Ngee Ann Polytechnic and the Dean's List at the National University of Singapore for excelling academically. At Officer Cadet School, he received the Sword of Honour, given to top cadets, marking a turnaround for Captain Pan.
The former gang member had been remanded twice in the Boys' Home - where residents include those who had committed offences when they were under 16, as well as those judged to be beyond parental control.
When he was 14, his mother had filed a complaint that the youngest of her four children was beyond parental control. He had been involved in gang fights, smoked in school and played truant.
But after he spent three weeks in remand and persuaded her to withdraw her complaint, she relented.
He was released but went back to his errant ways. By the time he was 15, he had committed offences such as housebreaking, possession of weapons and theft.
Worried he would commit more severe offences, Madam Ng went to at least four police stations to urge the police to expedite investigations and press charges.
In 2002, he was sent to the Boys' Home. His change "started with a thought" - when he decided to give school a try again.
"I knew I could not go on like this forever," he said.
After seven months in the Home, he was allowed to study at Queensway Secondary, though he had to return to the Home each day. Four months later, he was allowed to live in his own home, but had to report to a Boys' Home officer.
Although he hardly studied in Sec 1 and 2, he topped the Sec 3 level in his school.
Capt Pan, whose father works as an electrician, said his desire to change was sustained by the support of people such as his mother, who visited him at the Boys' Home each week, his aftercare officer, as well as staff and volunteers there.
Since his release, he has been volunteering on an ad hoc basis to give talks and mentor residents there.
Mr Kelvin Lua, 41, a former senior case worker at the Boys' Home and now head of voluntary children's home training at the Social Service Institute, said he is proud of Capt Pan for using his story to inspire others "who need to be told that it is possible to turn around".
Asked what he hopes to tell at-risk youth, Capt Pan urged them to start with small steps. He added: "Don't give up on yourself. Have a goal, and then go for it."
Correction note: This story has been edited to provide the correct name of Pan Wei Hao's mother Ng Saw Yong. We are sorry for the earlier error.