After all, couples who exercise together, stay together, so research suggests. We’ve enjoyed watching everything from their Dragon Boat Race to their London Marathon training competition.
There’s one sport Prince William just can’t match up to his wife in, though and that’s tennis.
In a recent interview, former tennis world number one, Rod Laver let the cat out of the bag about the Duchess Kate’s playing abilities.
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We had an idea about how good she was at tennis. After all, she was taught at the exclusive Hurlingham Club in London.
“I'd met William and Kate a few times, and in the Royal Box you get a chance to chat with them a little bit. They play tennis against each other. William told me he couldn't beat her.” Rod Laver told the Daily Mail in a recent interview.
It might not just be the Duchess of Cambridge that Prince William can’t beat.
It seems Prince George is a dab hand at the sport, too.
Roger Federer, who is an old friend of the Middleton family, even gave Prince George a private lesson at the Middleton family home in Bucklebury.
When asked about Prince George’s tennis aptitude, the current world number three said: “At that stage it's all about just touch the ball, it's already good. Same with my boys.”
Last year, according to Wimbledon Morning Coffee, the Duchess announced that Prince George’s favourite player was Roger Federer, which would have made their private lessons all the bit more fun.
He downplayed this information saying: “I think I have a little advantage that I actually spent some time, you know, with him. I'm the only player he's ever met. Then you have a little head start in who is your favourite player.”
He said he hopes the young prince still “feels the same in a few years’ time”. With the Duke and Duchess of Cambridge’s love of the sport, it’s likely he will.
With one future tennis player on their hands, Prince Louis’ first words being “Mary Berry” might give us an indication of where his path will lead as the young royals get older.
Duchess Kate’s busy schedule might certainly limit the amount of times she’s able to get on the court this month.
On Tuesday she joined a workshop run by the National Portrait Gallery's Hospital Programme, for her seventh official engagement in just over a week.