The Duchess of Cambridge knows how to work hard, but she also knows how to have fun! When she isn't sharing a sweet moment with kids or playing sports during official royal appearances, she can usually be spotted breaking out into laughter. And it's not just a half-smile pity laugh either; it's a show-every-single-one-of-your-teeth laugh. Honestly, her laughing face is so good, it's practically impossible not to crack a smile yourself. Based on these photos alone, we're pretty sure she never heard a joke she didn't like. Keep reading for all the times Kate caught a case of the giggles, and then look at the rest of the royal family's best laughing faces.