Kate Middleton is spilling the beans on which athlete her mother Carole Middleton has eyes for. The Duchess of Cambridge, who is the royal patron of Wimbledon, opened up in a new BBC documentary titled Sue Barker: Our Wimbledon, about her mom's secret crush on tennis player Roger Federer. "Roger [Federer] is my mother's heartthrob,” Prince William's wife revealed. “I don't think she will mind me saying that! I think he probably knows that too.” The Swiss athlete is a family friend of the Middletons, and he and his wife Mirka were guests at Pippa Middleton's wedding to James Matthews last month.

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VER GALERÍA Kate revealed that her mother Carole has a crush on tennis star Roger Federer Photo: Getty Images 

The 35-year-old royal also shared an embarrassing anecdote about her dad Michael, saying: "My father is not going to appreciate this, but we were walking past Tim Henman and we had just seen Sampras play. My dad said very coolly, 'Hi Pete.' I was mortified!"

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Tennis has been a part of Kate's life for quite some time. Prince George and Princess Charlotte’s mom admitted, "I have watched Wimbledon, that was very much part of my growing up. It's such a quintessential part of the English summer, and I think it really inspires youngsters, myself, it inspired me, when I was younger to get involved in the game. It hasn't changed either, I think that's what's so wonderful.”

VER GALERÍA The Duchess will appear in the new BBC documentary Sue Baker: Our Wimbledon Photo: Getty Images 

Kate and her husband Prince William are regular fixtures at the summer tennis tournament, however in 2013, the mother-of-two had to skip the men's singles final match when she was pregnant with her son. The then-mom-to-be asked her doctor if she could go but he told her "definitely not." "I was very heavily pregnant with George so I wasn't able to turn up," she said. "I wrote to [Andy Murray] afterwards saying sorry for not being there but huge congratulations."

VER GALERÍA The mother-of-two is the patron of the All England Lawn Tennis Club Photo: Getty Images 

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The sporty royal is featured in the new BBC documentary in her role as patron of the All England Lawn Tennis Club, a patronage she took over from the Queen last year. Kate will attend Wimbledon on Monday – her first time in the role. In the interview, the Duchess also revealed that her favorite tennis stars to watch growing up were Andre Agassi, Pete Sampras, Goran Ivanisevic and Steffi Graf, and that before she joined the royal family, she would queue up for hours to attend the tournament. "Being able to go into Wimbledon and be part of what is so amazing there, the atmosphere, is incredible, whether you're sitting on Henman Hill or are fortunate enough to be in one of the Center Courts," said Kate. "Every time Wimbledon is on I am thinking, 'Yes, I could do the same' and get out the racket. Sadly, never the same results."

Sue Barker: Our Wimbledon will air on Sunday, July 2 at 5.20pm on BBC One.

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