Ashlee Simpson's career may have been short-lived, but it sure was fun while it lasted. Beginning with her 2004 debut, Autobiography, she proved edgier and more rebellious than her older sister Jessica—still based in pop but with a heavier rock influence. She would spend less time in the spotlight than Jessica, despite also having her own reality-TV show, but Ashlee still left her mark with three albums that have sold close to four million copies.