Well, we can tell you first where she wasn't: with her man. The Prez was in Chi-town celebrating with Oprah (among others, but when Oprah's there, who else is really worth mentioning?), but his lady was no where to be seen.
So where was she? In Spain, with little Sasha. Where was Malia? Also not with Daddy. She's at summer camp, where she's only allowed to make one phone call (sound familiar, LiLo?) and rumor has it the little munchkin saved that phone call for her papa on his birthday.