Happy Birthday, Pippa Middleton! The Duchess of Cambridge's fashionable little sister kicked off her 29th birthday a day early with another visit to the U.S. Open last night, choosing a lemon, lace Phase Eight dress to cheer on the tennis champs. And it's only the latest look to add to a long line of great outfits, including a strawberry Hobbs mini, raspberry Issa double-take (her sister wore the same one in blue for her engagement photos!), and, of course, the ivory Alexander McQueen dress she wore to her big sister's wedding. Celebrate the royal-in-law—tennis enthusiast, colorful flats lover, and author-to-be—by taking a look back at all her best looks. Pip Pip, hooray!