Kate Middleton's close ties with Roger Federer shown by triple kiss

The Princess of Wales is a well-known sports enthusiast and the patron of several major sporting organisations, including the Rugby Football Union and the All England Lawn Tennis and Croquet Club (AELTC).

Kate is a familiar face at Wimbledon, where she enthusiastically joins in with the applause and is a fan of many of the players past and present, including Roger Federer, who she counts among her friends.

Their friendship seems to be quite strong, with Federer even attending the wedding of Kate's sister Pippa to James Matthews in 2017. That same year, Kate personally congratulated Federer on his Wimbledon victory, with Prince William by her side.

After Federer's triumph at Wimbledon, the then Duchess surprised fans by giving him not one, not two, but three kisses to celebrate his historic win. The delighted tennis star then shared a friendly handshake with Prince William.

It seems that Federer is more than just a casual friend in William and Kate's exclusive circle of celebrity pals. There were even rumours that he gave Prince George a private tennis lesson at the Middleton home in Bucklebury, reports OK!.

Federer later described the young Royal as a "sweet boy" with promising tennis skills.

The tennis ace isn't the only A-lister in Prince William and Kate's inner circle. They are also pals with David and Victoria Beckham, who were guests at the Royal wedding in 2011.

Then there are William's celebrity friendships, including Sir Elton John whose closeness to Princess Diana makes his bond with William almost destined.

Prince William's school pal Eddie Redmayne spilled some Eton beans by recalling: "I did play rugby with Prince William. I always felt a bit sorry for him because basically any school you played, all they wanted to do was tackle Prince William and they could say, 'I tackled Prince William'."

Not to be outdone, Kate has her own celebrity connection in the form of culinary legend and ex-Bake Off star Dame Mary Berry, with whom she's shared kitchen time. Mary even managed to get a few confessions about Kate's university days with William at St Andrews.