There are 613 members of Team USA, and at least fourteen of them share DNA. It's clear athleticism runs in the family for Phillip and Ryan Chew (badminton), Aria and Makenzie Fischer (water polo), Courtney and Kelley Hurley (fencing), Jessica and Nelly Korda (golf), Henry and Jackson Leverett (shooting), Kristie and Samantha Mewis (soccer), and Erik and Kawika Shoji (volleyball), who are all competing in this year's Olympic Games.
While competition has only just begun in Japan, here are the seven sets of siblings who are going for gold at the Tokyo Olympics:
Phillip and Ryan Chew
The Chew brothers from California began playing badminton tournaments together in 2018 and now they are heading to the biggest stage in sports for competition.
“Some people tell us they would never be able to play with their sibling but, for us, we do a good job at communicating with each other, whether it’s suggestions about our game or style, so it works out for the two of us,” Ryan, 24, told Reuters.
Brother, Philip, 27, competed in the 2016 Games, and both credit their grandfather, Don Chew, who founded the Orange County Badminton Club in 1996, for coaching them in the sport.
Aria and Makenzie Fischer
The Fischer sisters always knew they wanted to compete in the Olympics, just like their dad, Erich Fischer, who competed with the U.S. Men's National Water Polo team in Barcelona at the 1992 Games.
In 2016, Aria and Makenzie made that dream a reality when at 17 and 19 they became Olympic gold medalists in water polo. Together, they will compete again in Tokyo.
"I got a lot of motivation from seeing Makenzie grow up and starting to have success — just chasing her, wanting to be as good as her, and trying to be better than her," Aria shared in a USA water polo interview.
Courtney and Kelley Hurley
It hasn't always been family fun for U.S. Women's Fencing Team's Courtney Hurley, and sister, Kelley.
"When I was younger, it was more competitive between me and her, and when she got in there behind me I just thought 'C'mon, Courtney, this is my glory. Move on. Fence a different weapon or something.' It was very competitive between us for 2008," the older Hurley, 33, told USA Fencing in an interview. "But by 2012, we had definitely come to terms with our competition against each other and we joined forces with each other."
The sisters, who both graduated from Notre Dame University and are coached by their dad, earned a bronze medal in the London 2012 Olympic Games. The Tokyo Games will mark the fourth Olympic appearance for Kelley and third Olympic competition for Courtney.
Jessica and Nelly Korda
There is no sibling rivalry between golf stars Nelly Korda, 22, and big sister Jessica, 28.
"People like to put us against each other all the time to see if they can spark a rivalry or something," the older Korda sister told Golf Digest in a November interview. "But we just keep disappointing everybody."
The duo, daughters of tennis stars Petr and Regina Korda, aren't the only family athletes. Their brother Sebastian plays tennis professionally.
"My dad always said back in the day that golf was a retirement sport," Jessica told Golf Digest. "We’ve obviously completely changed his mind."
Henry and Jackson Leverett
Born just seventeen months apart, Henry and Jackson Leverett competed in their first shooting competition when they were 8 and 9 years old, respectively. Both students at Ohio State University, the brothers from Georgia have set four USA Shooting national records in junior men’s Rapid Fire and junior men’s Sport Pistol.
“It means a lot to me to have this experience with my brother,” Henry told USA Shooting.“It’s my first time in Japan and at the Games, so to have my best friend there with me is really comforting, especially when the competition and chaos begins.”
Kristie and Samantha Mewis
Two soccer star sisters will take the field in Tokyo together. Kristie Mewis, a 30-year-old Houston Dash midfielder, will team up with her younger sister, Samantha, a midfielder for the North Carolina Courage.
It won't be the first time the elder Mewis has taken the field in Japan; she played for Iga FC Kunoichi Mie in Japan’s women’s league in 2014. The Mewis sisters are the first to represent soccer for Team USA.
"I feel like the only thing that could have made me making it better was that Kristie made it too," Samantha told People earlier this month.
Erik and Kawika Shoji
Known affectionately as volleyball's 'Bro-jis', Erik Shoji and brother, Kawika, who is the team captain of the Men’s USA volleyball team, will make their second Olympic debut in Tokyo. The brothers, who hail from Honolulu, took home the bronze in Rio in 2016.
Parents, Dave and Mary Shoji, who both coached volleyball, will be cheering from their home in Hawaii.
"You know, we might need two different TVs going at the same time because Dave honestly makes it very difficult to watch with him because of that intensity," Mary Shoji told NBC affiliate Hawaii News Now. "Once in awhile I have to say, can you just please be quiet?”