George looked super-cute in a Breton-striped top, and even wore a sailor's hat for part of the regatta, while sister Charlotte wore a striped blue dress.
Charlotte almost stealing the show with her sassy antics, including blowing raspberries at photographers.
Kate and Wills were competing against each other all in the name of charity, with the Duke and Duchess of Cambridge skippering their own boats of six celebrity ambassadors.
It was TV personality Bear Grylls and his crew that took home the golden trophy, leaving Kate with a giant wooden spoon for her efforts on the waves.
But a great time was had by all!
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