Primary school student Paul Ma Chia-pao, 11, was determined to get his father to give up his 30-year smoking habit.
So he thought up a clever strategy - mixing the pressure of constant nagging and emotional blackmail with the promise of some nice treats at the end if he succeeded.
Paul's determination and inspired ideas helped him to win this school year's Smoke-free Home and Smoke-free Teens Campaign and a first prize of HK$3,000. He was one of more than 13,000 students, aged three to 15, who supported the campaign, organised by the Hong Kong Council on Smoking and Health (COSH).
Students at Hong Kong kindergartens, and primary, junior and secondary schools were asked to help create smoke-free homes in the city. They signed up 80,000 members of the public to back the campaign. Paul and other award winners also suggested ways to give up.
'I insisted that Dad and I browse many anti-smoking websites together every day until he could not take it anymore and said he'd quit,' says Paul, a Primary Six student at Po Leung Kuk Chee Jing Yin Primary School, in Sha Tin.
'I also developed a smoke-free slogan and plastered it all over our home as a constant reminder. Then I made an emotional appeal: I told Dad my doctor warned me that second-hand smoke was aggravating my respiratory problems.'
Paul also quietly replaced his father's cigarettes with cigarette-shaped biscuits. His happy father joked: 'It wasn't so hard to stop because of his constant nagging.'
Paul, who spoke of his campaign on a Hong Kong radio show, monitored his father's efforts each week for two months and offered to treat his father to a big meal if he managed to stop smoking for a month. He also promised to buy his father a prized digital camera - using his cash prize - if he gave up completely.
Paul came first out of 50 primary and junior secondary school prize winners who encouraged family members to stop smoking. The students received prizes for their efforts at a special ceremony at Citywalk, in Tsuen Wan, last month.
Lisa Lau, chairman of COSH, says: 'We were so excited to read stories of people giving up smoking.'
For more details, go to www.smokefree.hk