"Happy 38th birthday, Mary-Kate Olsen! It's hard to believe that the cute little girl from "Full House" is now a cool and stylish 38-year-old. Time sure flies when you're busy being fabulous and building a successful fashion empire. Here's to another year of slaying the game and making all of us wish we were part of the Olsen twins club. Cheers to you, birthday queen! Have a fabulous day filled with all the designer clothes and espresso shots your heart desires. #OlsenForever #AgeIsJustANumber"