They are siblings, rising badminton talents and have a dad who is a former national player.
Naturally, one might expect fierce rivalry among them, but only one of the three Wong siblings, the youngest, has expressed a wish to outdo his brother and sister in the sport.
Howin Wong, 13, admits that he sometimes sees his elder siblings - Jet, 17, and Crystal, 15 - as rivals, adding: "I want to beat them in competitions and win more medals than them."
The trio are enrolled in the Singapore Sports School - they were encouraged to do so by their father, former national badminton player Kenny Wong Kong Kay, 47 - and have each won medals at competitive levels in recent years.
Their oldest brother Jia Ren, a 19-year-old national serviceman, plays badminton only as a recreation sport.
Jet, who wants to be a psychologist, claims that he is "not as competitive as Crystal and Howin".
But can there really be no rivalry among siblings who are involved in competitive sports?
Sports psychologists tell SundayLife! sibling rivalry in sport, even if it exists, is seldom openly acknowledged.
Dr Jay-Lee Longbottom, 31, says: "For any siblings in sports, rivalry is something that's real and almost unavoidable. I think it's something many of such siblings, or even their families, keep quiet about and there is a lot of denial surrounding this.
"It should be addressed openly, which would help create a healthy sibling rivalry, where the focus is not placed on results, but things such as effort, attitude and etiquette."
Dr Longbottom, who works at Mental Notes Consulting, a partner of the Singapore Sports Medicine Centre, says her clients comprise mostly athletes who are under 18.
She reveals that she herself had felt a "healthy rivalry" with her twin Carly, as the pair previously played golf at competitive levels in Australia, where they are from.
When Dr Longbottom had to compete against her sister, she felt conflicted. While she thought she was the better player and had in fact beaten Carly in competition, she "also wanted her to do really well".
Not competing directly against one another is one explanation for a lack of rivalry among the Wongs, say Crystal and Jet Wong. The siblings generally compete in different age groups and are often further separated by girls and boys' events.
It is a different story for national bowlers and sisters Cherie and Daphne Tan though.
They had faced off for the first time in May this year at the Women's Open Masters finals of the 37th Malaysian International Open.
In the stepladder grand final, where the number of competitors is gradually whittled down, the younger Daphne, 24, was ahead initially but her 26-year-old sister eventually won the title.
Daphne says: "Usually, when she wins, I'm very happy for her. But for that particular competition, I was really sore."
Their mum, real estate agent Josephine Goh, 53, who describes the sisters as "inseparable", adds: "Daphne told me she was sore because she didn't win, not because her sister won."
The sisters had picked up bowling together 14 years ago after an impromptu Chinese New Year outing at the SuperBowl Jurong.
They train under former world champion and national head coach Remy Ong, who says he observed the sisters' "body language" during the final and thought they seemed "kind of lost" when they faced each other in competition.
"You don't really see rivalry between them. They're always there for each other," Mr Ong adds.
For national shooters Teh Xiu Yi, 18, and Xiu Hong, 20, competing in the same sport has brought them closer. There is no jealousy or rivalry, says their mother, Madam Teresa Chai, 46, a sales and marketing coordinator.
Xiu Hong, who heads for the Asian Games this month in Incheon, South Korea, took up shooting as a co-curricular activity in Secondary 1 and her coaches invited her sister to try out for it too.
Xiu Yi, a recent silver medallist in the mixed team 10m air pistol event at the Youth Olympic Games in Nanjing, China, says she and her sister "try to motivate each other", discussing techniques and performance.
Xiu Hong has a better personal best score (386) than her sister (382), but Ms Chai says she and her 47-year-old husband, who also have a 22-year-old son, do not compare their daughters.
As the Teh sisters have shown, having siblings compete in the same sport is not all about trying to outdo each other.
A spokesman for the Sports Psychology Department of the Singapore Sports Institute says: "They can be a source of invaluable support and encouragement. Ultimately, the athletes' relationship as siblings precedes their relationship in sports."
National taekwondo athlete Raja Zulfadli Raja Mahmod, 21, can often be seen on the sidelines during training and competitions, guiding and urging on his 19-year-old brother and teammate, Arshad.
Arshad, who fights in the under-63kg bantamweight category, recalls: "During training, whenever I'm at the lowest point, he would keep pushing me."
At the 18th Asian Cities Gold Cup Taekwondo Championships in Hong Kong in February, Arshad reveals that "flashbacks" of those training sessions helped him fight his way to a silver medal. Zulfadli himself clinched gold in the under-74kg lightweight division.
On top of their training, the two often spar at their Woodlands four-room HDB flat, after pushing the furniture aside. The medals they have won have inspired younger siblings Rafie, 18, and Nurliyana Izzati, 12, to also take up the sport.
Training and entering competitions together have also brought wakeboarders and siblings Sasha, 21, and Matthew Christian, 23, closer. "We've learnt how to read each other without saying much," says Sasha.
For instance, if she does "badly" in a competition, like at the 2011 world championships where she was placed sixth, her brother would "just take my wakeboard, which he doesn't usually do, and walk in front of me," Sasha adds.
That, as they say, is the unspoken bond that exists between siblings.
This article was first published on Sep 14, 2014.
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