By Scott McDonald | July 29, 2016, 3:25 p.m. (ET)

Venus and Serena Williams celebrate victory in the women's doubles final against Timea Babos of Hungary and Yaroslava Shvedova of Kazakhstan at the Wimbledon Lawn Tennis Championships at the All England Lawn Tennis and Croquet Club on July 9, 2016 in London.


Athletes don’t become Olympians just by luck. Years of hard work begin somewhere, and more often than not it starts against a familiar foe.

Brothers battle brothers and sisters battle sisters, all for supremacy and bragging rights. Sometimes both siblings develop into great, or even world-class, athletes.

Seven sets of siblings will represent Team USA in Rio de Janeiro at the upcoming Olympic Games. It’s more than a family affair. For most, it’s a way of life.

“When I first found out I made the team it was so emotional and exciting,” said Aria Fischer, a member of the women’s water polo team going for its second straight gold. “But getting to experience it with my sister [Makenzie], that emotion was 10 times greater. She’s my sister and my best friend.”

Siblings who grow up close in age often become best friends, much like indoor volleyball brothers Erik and Kawika Shoji. Kawika said it’s nice to have family there, because as great of an experience it is, there still can be down times.

“It’s really a neat thing because we’re not only able to enjoy the good times, the wins, medals and now the Olympics, but to be there for each other in the down moments,” said Kawika, who has played at the club, collegiate and professional levels with Erik leading up to their Olympic debuts. “It’s validation of a lot of hard work we put into it.”

From the pool to the courts to the fencing arena and playing fields, here are America’s siblings with sights set on gold.

Mike Bryan and Bob Bryan celebrate after defeating Ivan Dodig of Croatia and Marcelo Melo of Brazil in the men's double final during the Citi Open at Rock Creek Park Tennis Center on Aug. 9, 2015 in Washington, D.C.


Bob and Mike Bryan (tennis):

Bob and Mike Bryan have been in sync ever since they were born three minutes apart. They’re the only duo to win every Grand Slam event at least twice, and they claim the so-called “Bryan Golden Slam” after adding an Olympic gold medal to their list of accomplishments. The brothers own almost every men’s doubles record kept by the World Tennis Association, and it’s why they’re a favorite to win gold in Rio.


Aria and Makenzie Fischer (water polo):

Neither of these sisters has even been to college. That changes this year, as Makenzie will enroll at Stanford University. Aria will be a senior this fall at Laguna Beach High School, where the sisters won back-to-back CIF-SS Division I championships — equivalent to a state championship in smaller states. Makenzie is a defender and Aria plays center, which matches them against each other in practice, where their elbows, knees and ankles joust underwater.

“I’ve never been on a water polo team without her,” Makenzie said. “We know each other well, and we always look for each other when we’re out there together. But we’ve got so many great teammates so we’re excited.”

Their father, Erich Fischer, played on the 1992 U.S. Olympic water polo team that finished fourth.

Kelley and Courtney Hurley celebrate winning the bronze medal match 31-30 against Russia during the women's epee team fencing finals at the London 2012 Olympic Games at ExCeL on Aug. 4, 2012 in London.


Courtney and Kelley Hurley (fencing):

The Hurley sisters were the first U.S. siblings to qualify for Rio. Though this won’t be the first Olympic Games for either, it’ll be the first time they can compete against each other. Kelley finished 20th at the 2008 Games in Beijing and Courtney finished 22nd in London, where they were both part of the bronze-medal-winning team. They are the top two Americans in epee fencing and will compete in both individual and team events in Rio.


Margaux and Isabella Isaksen (modern pentathlon):

Margaux, 24, enters her third Olympic Games after finishing fourth in the 2012 London Games and 21st at the Beijing Games. Isabella, 22, joins her sister and readies for her first Olympic Games.


Julia and Katie Reinprecht (field hockey):

The Reinprecht sisters began their journey several years ago on the fields of Mount Saint Joseph Academy in Pennsylvania, and both went on to play at Princeton University. Now midfielder Katie and defenseman Julie appear in their second Olympic Games together. They placed 12th at the 2012 Games and were part of the team that won Champions Trophy bronze earlier this year, the team’s first medal at the event in 21 years.


Erik and Kawika Shoji (indoor volleyball):

The brothers from Honolulu played club volleyball together but went to different high schools. They rejoined forces at Stanford University and won a national championship in 2010, when Kawika was named the NCAA Division I national player of the year. The two play professionally in Europe, even playing one year together in Berlin.

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“A lot of time was spent around the sport with our family,” said Kawika, whose father enters his 42nd year as the women’s volleyball coach at the University of Hawaii and is the NCAA all-time wins leader.

Kawika, a setter, calls Erik “one of the best liberos in the world.”

 
Venus and Serena Williams hold their trophies following victory in the ladies' doubles final at the Wimbledon Lawn Tennis Championships on July 9, 2016 in London.


Serena and Venus Williams (tennis):

If any American siblings could survive on a first-name basis it would be Serena and Venus. Their names are globally known for tennis and beyond, and they will be favorites to medal in Rio. They are the winningest doubles team in Olympic history with three gold medals (2000, 2008, 2012). Serena, whose 22 Grand Slam titles tie her with Steffi Graf for the most all-time in the Open Era, won individual gold in 2012 and will look to become only the second player to ever win at least five gold medals in tennis. Venus could also match that feat as she won individual gold in 2000.






Scott McDonald, who has 18 years of experience in sports reporting, was named the State Sports Writer of the Year in 2014 by the Texas High School Coaches Association. McDonald is a freelance contributor to TeamUSA.org on behalf of Red Line Editorial, Inc.