Alyson Hannigan is an American actress and television presenter. She is best known for her roles as Willow Rosenberg on the television series Buffy the Vampire Slayer (1997–2003), Lily Aldrin on the sitcom How I Met Your Mother (2005–2014) for which she won a People's Choice Award in 2009, and Michelle Flaherty in the American Pie film series (1999–2012). Hannigan was born in Washington, At age four, Hannigan began appearing in commercials. She moved to Hollywood at age 11.Living with her mother and attending North Hollywood High School, she successfully auditioned for agents while visiting her father in Santa Barbara. After attending North Hollywood High School, she attended California State University, Northridge. Hannigan's first major film role was in My Stepmother Is an Alien, a science-fiction comedy released in 1988. In 1989, her first regular role on a TV series came when she was cast in the short-lived ABC sitcom Free Spirit. In 1997, Hannigan was cast to play Willow Rosenberg, Buffy Summers' best friend, on the television series Buffy the Vampire Slayer. The show became a success, and Hannigan gained recognition, subsequently appearing in several films aimed at teenaged audiences, including American Pie (1999), Boys and Girls (2000), American Pie 2 (2001), and American Wedding (2003). In 2012, Hannigan reprised the role of Michelle in American Reunion. Since 2016, Hannigan has hosted the television series Penn & Teller: Fool Us.
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