Last year, he started noticing an elderly man with a hunched back pulling a luggage near his souvenir stall in Sago Street, in Chinatown.
Then on one night early this year, he saw the man sitting by the roadside, clutching his chest and having trouble breathing.
The souvenir seller, who wanted to be known only as Mr Yep, went to check if the man needed help.
"I was worried that something might happen to him, so I went over to speak to him," the 63-year-old told The New Paper on Wednesday.
When the man kept gesturing to the main road without saying a word, Mr Yep realised that he was speech impaired.
It took a while before he found out the man wanted to go to the bus stop about 200m away.
Mr Yep then took out his trolley and placed the man's bag, which he estimated to weigh 10kg, on it. He helped the man sit on the luggage and pushed them to the bus stop.
This act of kindness would turn into a routine from that night.
The next evening, he saw the elderly man waiting outside his stall and understood that he was asking for help again.
Mr Yep duly obliged, and has been doing this almost daily for the past six or seven months - even waiting for the bus to arrive and making sure the man gets a seat before leaving.
Then early last month, it occurred to Mr Yep that it was not feasible for him to keep helping the man.
"What if I fall sick one day and I am not around to help him? It is dangerous to let him walk around in his state," he said.
He decided to contact Shin Min Daily News to see if the Chinese evening newspaper could trace the man's family.
A reporter then met the man, who had a piece of paper with his nephew's phone number.
When Shin Min Daily News contacted the nephew, he said his uncle, 67, was a stubborn man who would insist on leaving the home every day.