Although they began their careers around the same time, younger sister Hilary became a teen idol years before Haylie made her mark. The senior Duff started out as a singer-songwriter, but quickly added acting to her résumé with a handful of big- and small-screen appearances, including a two episode stint on Lizzie McGuire, Hilary's hit TV series. A part as a popular pretty girl in the 2004 cult comedy Napoleon Dynamite got her some attention sans sibling, as did a recurring role as a pregnant college student on the last season of 7th Heaven.