The best man's speech at a wedding often gets the most laughs on the day, and in his memoir, Spare, Prince Harry shared the gentle ribbing he gave Prince William during his speech at the Prince and Princess of Wales' wedding.
While Prince Harry was not the best man, his brother did ask him to perform a speech at the reception, with the Duke of Sussex revealing he told "a silly story about Willy's days playing water polo."
Silly though the story may have been, Prince William was in fact a dedicated water polo player in his younger years, even playing competitively. The Prince of Wales was captain of the water polo team during his time at the University of St Andrews, frequently travelling around the country to play other student teams.
William made his international water polo debut in 2004, taking to the pool for the Scottish National Universities side at a competition in Cardiff. Sadly, his team lost 14-7, but not through any fault of William's, with Welsh captain Oliver Newcombe saying the future King "gave as good as he got. We didn't single him out for any special treatment. Water polo is a hard sport to play."
The Prince of Wales' love of splashing about was acknowledged in 2007 when he was appointed patron of the English Schools' Swimming Association.
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"Having swum and played water polo throughout my days at school and university, I am well aware of the great benefits and pleasure that can be derived from them," he said at the time.
"As patron, I look forward to doing whatever I can to help children and young people in England become more physically active and healthy through fostering their enjoyment of swimming, diving and water polo."
While water polo isn't a commonly played sport in the UK, we can see why Princess Kate's husband likes it. It's fantastic for building endurance, as players are not allowed to touch the bottom of the pool and have to tread water the whole time.
They also have to wrestle the ball from other players and guard against opponents, meaning the game is far from easy.
Being a good swimmer is key to playing water polo, and William, along with many other members of his family is skilled in the water. He represented Eton in swimming, and it seems that his children, Prince George, Princess Charlotte and Prince Louis are taking after him.
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He shared in 2017 that the royals were a "family of swimmers," telling Eileen Fenton, who received an MBE for voluntary services to swimming all the details of their prowess.
Eileen told the Press Association: "He said that he and his wife make sure the children can swim and they all go and they swim quite well."
Prince William likely inherited his swimming prowess from his grandmother, Queen Elizabeth II, who reportedly earned several lifesaving certificates in her girlhood as well as achieving a badge recognising proficiency and grace in every stroke and in diving.
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