It was the first time the siblings had gone on holiday together and it was Mr Tan Ah Hiang's first overseas trip in years.
The 55-year-old even had a new passport made just for the trip to Sri Lanka.
But tragedy struck on March 17, when he and family members were hiking up Adam's Peak in south-western Sri Lanka and Mr Tan died of a heart attack.
Mr Tan, the fifth of nine children, was on holiday with his older brother, Mr Tan Ah Boon, younger sister, Madam Tan Bee Chin, and her husband, Mr Low Tiong Meng.
The bachelor had recently bought a three-room flat in Bukit Batok and had moved there in October after living with another sister for most of his life.
Speaking to The New Paper yesterday, Mr Tan Ah Boon said that in the wee hours of March 17, the Buddhist tour group of about 20 started their ascent of Adam's Peak to catch the sunrise. They had arrived in Sri Lanka on March 13.
Mr Tan Ah Boon said the holiday was arranged by a few Buddhist friends who wanted to take the opportunity to make a pilgrimage. The siblings decided to make a holiday of it and went along, even though Mr Tan was not particularly religious.
The 2,243m-high Adam's Peak, also known as Sri Pada, is in Sri Lanka's Central Highlands, about a four-hour drive from the capital Colombo.
It is said to be a holy site and is a popular destination for Buddhist pilgrims. Muslims and Christians also believe the mountain to be of special significance.
There were lights to illuminate the way at night and much of the route had cement and stone steps.
"All along the way, there were rest stops where you could buy food and drink. There were even police posts stationed along the way in case anyone was in trouble," said Mr Tan Ah Boon.
The group started their trek shortly after midnight.
At about 3.30am, after a 5km hike, Mr Tan began to have breathing difficulties and collapsed.
Said Mr Tan Ah Boon: "My brother overtook all of us so he was quite far in front. Then we heard that someone had 'fallen' and as the police officers were carrying him down on a stretcher, I saw that it was my brother."
Mr Tan had been about 30 minutes from the peak, his brother said.
He died on the way to hospital.
"We were all shocked because it was so sudden. Even our driver cried when he heard the news," said Mr Tan Ah Boon, who said the men became fast friends during the trip.
He added that the family was grateful to a nearby temple, which lent them a car to travel around after the tragedy, as well as the Singapore Consulate-General in Colombo, who helped arrange for Mr Tan's body to be flown back on the same flight as his siblings on March 18, the date they had originally planned to return.
Mr Anil Jeyasinghe, the officer in charge of the Nallatanniya Police Station that handled the case, told The New Paper that a post-mortem conducted at a local hospital showed that Mr Tan had died of a heart attack.
He said that in this year alone, four people have died while climbing up Adam's Peak, most of them from heart attacks.
"It doesn't matter what your age is, you must be in good health. At the base of the mountain, you can see for yourself how steep it is, then you decide whether you want to go," he said.
It used to be more difficult to scale the peak.
Pilgrims even had to use ropes to get to the top, where there is a crater which Buddhists believe to be Buddha's footprint, said Mr Jeyasinghe.
He added: "Me and the other officers hike the entire trail before the start of the Poya (a Sri Lankan festival usually between February and March) so we know the route is safe."
As for Mr Tan Ah Boon, he said the family is trying to move on from Mr Tan's sudden death.
"I suppose you could say it was fate," he said.