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 film and TV appearances, including a two-episode stint on Lizzie McGuire, Hilary's hit Disney Channel series. The part of popular pretty girl Summer in the 2004 cult comedy Napoleon Dynamite got her some attention sans sibling (and a Teen Choice Award), as did a recurring role as a pregnant college student on the last two seasons of long-running family drama 7th Heaven. Since then, Duff has starred in a number of direct-to-DVD movies, including the thriller Backwoods and the black comedy Legacy.
- Studied ballet from an early age in Texas.
- Prime-time guest appearances early in her acting career included Chicago Hope, Boston Public and Third Watch.
- Co-wrote two songs on sister Hilary's 2003 debut album, Metamorphosis, as well as one track on her 2007 release, Dignity.
- Joined Hilary to portray the Shangri-Las on an episode of NBC's American Dreams in 2003.
- Appeared in commercials for Mattel's Barbie and Hershey's Ice Breakers.
- Enrolled in the Harvard Extension School through the Distance Learning Program in 2005.
- Starred in two movies from the Hallmark Channel's popular Love Comes Softly Saga in 2009: Love Finds a Home and Love Takes Wing.
- Susan Duff — Mother
- Bob Duff — Father
- Ryan — Daughter
- Hilary Duff — Sister
- Matt Rosenberg — Fiancé
- Nick Zano — Ex-significant Other
- Birth Name: Haylie Katherine Duff
- Birth Place: Houston, Texas, United States
- Birthday: February 19, 1985, Aquarius
- Profession: Actor, Singer