Kate Middleton Cracks Up, Has a Ball With Prince William, Prince Harry at Children’s Charity Event: Adorable Photos!

Prince William, Prince Harry, and Kate Middleton laughing
Kate Middleton had a ball while attending a children's charity event with Prince William and Prince Harry in London on Monday, Oct. 26 Tim Ireland - WPA Pool/Getty Images

Letting her hair down! Kate Middleton had a ball while attending a children's charity event at BAFTA's headquarters in London's Piccadilly on Monday, Oct. 26. The mum of two was joined by her husband, Prince William, and brother-in-law Prince Harry to support the animated special Shaun the Sheep: The Farmer's Llamas.

kate middleton welly wanging
Kate Middleton takes part in welly wanging with children during a meeting of the Charities Forum at BAFTA on October 26, 2015 in London Tim Ireland - WPA Pool/Getty Images
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Kate Middleton takes part in welly wanging with children during a meeting of the Charities Forum at BAFTA on October 26, 2015 in London Tim Ireland - WPA Pool/Getty Images

Clad in a fit-and-flare Tabitha Webb dress, Middleton, 33, took part in several activities. The sporty Duchess — who famously played lacrosse while attending St. Andrews — had some young competition as she played a round of welly wanging at the event. (During the game, players try to throw Wellington boots within boundary lines, which are located a few feet away.)

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Prince William poses for photos wearing a Shaun the Sheep hat at a meeting of the Charities Forum at BAFTA on October 26, 2015 in London Tim Ireland - WPA Pool/Getty Images

The Duke of Cambridge, 33, and his younger brother, 31, stood behind Middleton as she played, and couldn't stop laughing. They, too, joined in on the fun.

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Prince Harry poses for photos with a child at a meeting of the Charities Forum at BAFTA on October 26, 2015 in London Tim Ireland - WPA Pool/Getty Images

"Kate admitted her effort was hopeless," an onlooker tells Us Weekly.

Nevertheless, Prince William also showed off his sweet daddy skills. At one point, he wore Shaun the Sheep: The Farmer’s Llamas hats with children at a crafts table. Prince Harry, in particular, kept one wheelchair-bound child in stitches while speaking with him.

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Kate Middleton plays with a little girl at a meeting of the Charities Forum at BAFTA on October 26, 2015 in London Ian Vogler - WPA Pool/Getty Images

But that's not all. The royal family also watched four school children put on a cute performance. At one point, the kids made it appear like they had stepped inside a suitcase on stage.

kate middleton reading to little girl
Kate Middleton reads with a little girl during a meeting of the Charities Forum at BAFTA on October 26, 2015 in London Ian Vogler - WPA Pool/Getty Images

"Kate joined one little girl on stage and the pair filmed the last scene," the source adds. "William joked, 'Make Catherine do a silly walk.'"

Up next, the trio will attend the world premiere of Spectre at the Royal Albert Hall in London on Monday night.

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