Hayden Leslie Panettiere (born August 21, 1989) is an American actress, singer, and Grammy Award nominee. She is perhaps best known for her role on the NBC series Heroes as Claire Bennet. She also appeared as the voice actress for the role of Kairi in the Square Enix Kingdom Hearts series.

Early life and family
Born in Palisades, New York, Panettiere is the daughter of Lesley R. Vogel, a former soap opera actress, and Alan L. "Skip" Panettiere, a fire department lieutenant.She has one younger brother, fellow actor Jansen Panettiere.

Education
Panettiere attended South Orangetown Middle School in New York but following 7th grade, finished her high-school education via home schooling and has postponed higher education in favor of an acting career, although she has expressed an interest in "continuing to learn."

Actress
Panettiere began modeling at the age of 5 months. She then began appearing in commercials at 11 months, first appearing in an advertisement for Playskool. She landed a role as Sarah Roberts on the ABC soap opera One Life to Live (1994- 1997) and later as Lizzie Spaulding on the CBS soap opera Guiding Light when she was seven years old (1996 - 2000). While on Guiding Light, Panettiere's character Lizzie battled leukemia. The show received a Special Recognition Award from the Leukemia and Lymphoma Society for bringing national awareness of the disease to the attention of daytime viewers.

Hayden Panettiere in 2007
Panettiere appears as Claire Bennet in the NBC series Heroes as a high school cheerleader with regenerative healing powers. Due to her role on Heroes, she became a regular on the science fiction convention circuit, invited to attend conventions around the world in 2007, including New York Comic-Con and Fan Expo Canada. In regards to the roles she has played, Panettiere admitted that options are sometimes limited because "people look at [her] as either the 'popular cheerleader' type or just 'the blonde'." She has appeared in over a dozen full-length feature films, as well as several made-for-TV movies. She provided the voice for Dot in the Pixar CGI animated movie A Bug's Life for Disney. In addition, she appeared as the voice of Kairi in the Kingdom Hearts series of video games for the Playstation 2.
Panettiere appeared on FOX's Ally McBeal as Ally McBeal's daughter, and had a recurring guest role on Malcolm in the Middle. She guest starred in Law & Order: SVU and played Sheryl Yoast in the film Remember the Titans. She starred in Bring It On: All or Nothing as a cheerleader and had a supporting role as Adelaide Bourbon in the recently released independent film Shanghai Kiss.
She appeared in the upcoming drama film Fireflies in the Garden as a younger version of Emily Watson's character, Jane Lawrence. In June 2007, she signed with the William Morris Agency, after previously being represented by United Talent Agency.Forbes estimated that she earned $2 million in 2007.
In early 2007, Panettiere appeared on the syndicated Ashton Kutcher-produced show, Punk'd. The appearance was engineered by her mother and involved a male "fan" discussing her work with her, instigating a jealous reaction from the man's spouse.

Singer
Panettiere was nominated for a Grammy in 1999 for Best Spoken Word Album for Children for A Bug's Life Read-Along [2000].Panettiere is featured on the soundtrack to Bring It On: All or Nothing alongside her co-star Solange Knowles. She recorded a song titled "Try" for the 2007 Bridge to Terabithia soundtrack. She recorded a ballad for Cinderella III: A Twist in Time called "I Still Believe."

Endorsement
In late 2006, Neutrogena made Panettiere the cover girl for their new worldwide ad campaign; following in the footsteps of actresses Kristin Kreuk, Josie Bissett, Jennifer Love Hewitt, Mandy Moore, Mischa Barton, Gabrielle Union and Jennifer Freeman. In September 2007, Panettiere appeared in a Got Milk? ad photographed by Annie Leibovitz.

Personal life
In 2006, Panettiere began dating Stephen Colletti, the former Laguna Beach: The Real Orange County, star. The couple broke up in September 2007. In December 2007, it was widely reported that she was dating her Heroes costar Milo Ventimiglia, though Panettiere has denied that these reports in an interview with GQ.

Activism
On October 31, 2007, Panettiere was involved in a confrontation between Japanese fishermen and five other surfers from Australia and the United States (including former Home and Away star Isabel Lucas), as the group tried to disrupt the annual dolphin hunt in Taiji, Wakayama. The confrontation lasted more than ten minutes before the surfers were forced to return to the beach, after which they left the country. The fisherman consider the condemnation as an attack on their culture.
Panettiere told E! News that an arrest warrant has been issued in Japan for her interference in the dolphin hunt. In November 2007, she was awarded the "Compassion in Action Award" from the animal rights group PETA for her efforts to stop the dolphin hunt in Japan. She is also a vegetarian.
On January 28, 2008, Panettiere handed a letter of protest to the Norwegian ambassador in the United States arguing that Norway should stop its sustainable hunt for whales. She also delivered a letter to the Japanese ambassador calling for the end of Japan's "Scientific Hunt" of whales. The following day, she also appeared with Chairman Nick Rahall, Chris Shays and John Kerry at a press conference calling for the Bush Administration to stand firm at the next IWC meeting.

Source: wikipedia