Athletes, in their relentless pursuit of excellence, seldom talk about regrets, only the next race, the next round. But for swimmer Quah Ting Wen, one incident stands out.

Her decision to surf in November 2011 did not just leave her with two fractured bones in her left forearm. Nor did it just dash her hopes of qualifying for the 2012 London Olympics.

The biggest blow for the 23-year-old was that it shattered a long-held dream of competing on sport's grandest stage with her brother Zheng Wen, who was making his Games debut.

But that dream will be realised in Rio de Janeiro this month as both will take to the pool at the Olympic Aquatics Stadium.

Ting Wen was awarded the universality spot as no female Singaporean swimmer had qualified while Zheng Wen, 19, made the cut for three events (100m backstroke, 100m and 200m butterfly).

They will be the sixth pair of siblings to represent Singapore at the Olympics.

"Ever since we started swimming, it has always been our goal to be able to represent Singapore at the Olympics together. We missed out in 2012, so to be able to do it this year is just great," said Ting Wen.

Zheng Wen added: "It's one thing to represent Singapore at the highest level, but to be in Rio with someone who's been with me every step of the journey is a really nice feeling."

The three Quah siblings, including younger sister Jing Wen, 15, are a tight-knit bunch and spend a lot of their time together at home.

While Ting Wen was the first to make a splash on the international stage, starting with a five-gold haul at the 2009 SEA Games, she readily admits turning to Zheng Wen for inspiration and comfort during major Games.

After all, while Singapore is making inroads in the global arena, it still lacks a significant presence at the biggest meets, highlighted by the three-strong swimming contingent in Rio, which includes Joseph Schooling, 21.

This is why, Ting Wen said, when sitting in the call room where "everyone is staring each other down", it helps to know her brother is "somewhere in the building".

"He's seen me at my best and worst and is someone I can truly open up to," said Ting Wen, who will compete in the 100m fly.

"I don't like showing my fears and weaknesses to other people but he usually understands how I feel before I even say anything. I just release all my troubles on him but he's really tough."

For the indomitable Zheng Wen, all tense and locked in on the race, it helps to have his elder sister around to soothe his nerves.

He said: "She'd pat my shoulder and tell me to have a good race. It sounds simple, but a hug from her is all I need before I race."

With both Zheng Wen and Jing Wen eyeing qualification for the 2020 Olympics, will Ting Wen join them on the campaign trail?

For now, she is keeping her cards close to her chest. The holder of three national records (100m, 200m free, 400m individual medley), said: "Tokyo is still far away, but it'd be cool if all of us were in Japan together."

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