Hilary Duff was born on Sept. 28, 1987, in Houston. She was born to Robert Erhard Duff and Susan Colleen Cobb, owner of a chain of convenience stores and a stay-at-home mom, respectively.
At a very young age, Duff's mom encouraged her to take an acting class with her older sister, Haylie. The girls studied Checchetti ballet and both performed in "The Nutcracker Suite" with the Columbus BalletMet in San Antonio.
Soon afterward, Duff's mother moved with the girls to California to pursue their potential acting careers. Their dad stayed behind to run the family business.
After being in California for a few years, the sisters were both cast in several television commercials.
Duff's first few roles were fairly small, including an uncredited appearance in the 1996 miniseries, "True Women" and a role as an extra in the comedy-drama "Playing By Heart."
Her first big part was that of Wendy in the direct-to-video movie, "Casper Meets Wendy."
In 1999, Duff won a supporting role in the television movie, "The Soul Collector." She ended up winning a Young Artists Award for best performance in a TV movie.
In 2000, Duff and teen pop singer Aaron Carter started dating. Their relationship went on for a year and a half before he reportedly broke up with Duff for Lindsay Lohan. Carter would date Duff again, though, after splitting with Lohan, which would spark what the media portrayed as a feud between the two Disney stars.
In 2000, Duff was cast as one of the kids in the NBC's "Daddio," also starring Michael Chiklis. However, she was dropped from the cast before the show even went to air. Duff admitted at that point that she was reluctant to continue with acting, but her mom and manager encouraged her to keep going.
It was then that Duff won her star-making role as Lizzie McGuire in the Disney Channel show, "Lizzie McGuire," in 2001. The show became hugely popular, drawing 2.3 million viewers per episode.
In 2002, Duff expressed interest in a musical career, and Disney backed her recording the song "I Can't Wait" for the "Lizzie McGuire" original soundtrack. After 65 episodes and a film spin-off, "The Lizzie McGuire Movie," in 2003, Duff's contract expired and she rejected the idea of continuing the character any further.
Duff's second movie was in the independent film, "Human Nature," in 2002, also starring Patricia Arquette. Soon afterward, she starred in the Disney Channel movie, "Cadet Kelly." The movie became the channel's most-watched program in its 19 years on the air.
That same year, Duff released her first album, "Santa Claus Lane," a collection of Christmas songs that reached No. 3 on the children's music charts and barely reached the bottom of the Billboard 200 album charts. The title track was used in "The Santa Claus 2" with Tim Allen.
Duff had her first major feature role in "Agent Cody Banks" in 2003 alongside teen actor Frankie Muniz of "Malcolm in the Middle."
Next, Duff played one of Steve Martin's 12 children in the movie, "Cheaper by the Dozen." This was her highest-grossing film, and it spawned a 2005 sequel in which she was also featured. The sequel failed to do as well as the original.
In 2003, Duff released her first non-holiday album, "Metamorphosis." It hit No. 1 on U.S. and Canadian charts and has sold over 3.7 million copies. The single "So Yesterday" was a Top Ten hit in various countries, and "Come Clean" became Duff's first Top 40 U.S. hit.
In 2004, Duff starred in "A Cinderella Story," which had average sales at the box office. Although it seemed her career was soaring, Duff's next film, "Raise Your Voice," would prove to generate a largely negative response from critics, mainly with regard to her vocals. It remains her least successful film so far.
Despite the criticism, Duff went on to release her third album, "Hilary Duff." It debuted at No. 2 in the U.S. and has sold over 1.5 million copies. She also started her own clothing line called "Stuff by Duff."
In 2005, amid music success, the pop princess returned to the big screen, starring in her familiar role as a teenage daughter alongside Heather Locklear in "The Perfect Man," but the movie did poorly at the box office.
Later that year, Duff released her fourth CD, "Most Wanted," which included songs from her previous two albums along with new songs inspired by various rock bands. The entire album was co-wrote and co-produced by Duff and her new boyfriend, Joel Madden of "Good Charlotte." The single "Wake Up" became her highest-peaking single in the U.S. The album debuted at No. 1 on the Billboard chart.
In 2005, Duff donated $250,000 to those affected by Hurricane Katrina. She is a self-acclaimed animal rights activist, a member of "Kids with a Cause" and serves on the Advisory Board for the Audrey Hepburn Child Benefit Fund.
There were reports in 2005 that Duff had veneers put in because she had chipped teeth from microphones during performances. The same year, the press criticized her for losing weight, causing speculation that she had an eating disorder. Duff denied all claims, saying that she had just been exercising more often.
In 2006, Duff starred in "Material Girls," where she and Haylie Duff played spoiled heiresses whose lives change radically when their family loses its fortune.
After two and a half years together, Duff and Madden split up. Madden later told the press that the six-year age gap was difficult for them. Madden would start dating Nicole Richie, daughter of soul star Lionel Richie, in early 2007.
Duff released her latest record, "Dignity," in March 2007, which featured songs co-written by Pink and her older sister. She has said it has a more "dancey" feel to it, though the 19-year-old's album cover shows her with a more serious, subdued and mature look than on her other albums.
She told the Associated Press that the album had "a new side of me and part of me. All the songs are so self-explanatory. It was very liberating."
For her hit single on the album, "With Love," Duff won the People's Choice Favorite International Artist category at the 2007 MuchMusic Video Awards.
Duff plans to launch a juniors clothing line in fall 2007 for her label "Hilary Duff."