When he turned 16, Wong Jun Sheng did not receive the usual birthday gift from his father.
What he received was a signed consent form so that he could donate blood.
Blood donors below 18 are required to get consent forms signed by their parents or guardians. But you have to be at least 16 to be able to donate blood.
Since he was "really small", said Mr Wong, he had always wanted to follow his father's example and finally got his wish.
Mr Wong, who is now 21, said: "When I was younger, I would notice the small strips of bandages on my dad's arm. So I started asking him how he got those plasters.
"That was when I found out that he had been donating blood and he also started to encourage me to donate."
Mr Wong, now 21, has donated blood 20 times during the past five years. He said his father has donated blood more than 100 times.
His 17-year-old brother, Jun Da, who is waiting to enrol at the Nanyang Academy of Fine Arts, was diagnosed with leukaemia when he was nine. Jun Da wanted to donate blood, too, but is a recipient instead.
Said Mr Wong: "That (diagnosis) was eight years ago, before I started donating blood. Seeing my brother suffering (from leukaemia) as a kid made me want to donate even more.
"Somehow, some way, I hoped that my blood would benefit him."
Different blood type
The brothers do not share the same blood type, so Jun Da cannot benefit directly from his brother's donations.
But they share a close bond and often play video games together.
Mr Wong, who graduated from Nanyang Polytechnic's mechatronics engineering course this year and is waiting to enlist for national service, said he would always keep a lookout for his younger brother and would get paranoid when he is not in his bedroom.
"But I have to say, if I were in his (Jun Da's) shoes, I don't think I would be sitting here right now. I'm not as strong as he is and I don't have so much will power."
Jun Da, who is now in remission, said: "We've been close since young. I think of this illness (leukaemia) as a blessing in disguise.
"It has made my life slower in a sense and made me appreciate my family even more. It has also helped me mature."
Today, the Wong brothers are active volunteers at the Youth Donor Club under the Singapore Red Cross, advocating the importance of blood donation and how it can save lives.
The club conducts roadshows and its youth volunteers are sometimes invited to speak to students at schools to encourage them to donate blood.
"Even though I can't donate (blood), I feel happy to be able to help too," Jun Da said.
This article was first published in The New Paper.