As a child, Katie took gymnastics, studied piano, guitar and singing, then took dancing and acting lessons and eventually became a cheerleader for the California Flyers.
Katie had just been accepted to 'Tisch' at NYU when she was offered her first role as "Dee Dee", which was one month before graduating. Katie's early exposure to show business, the cosmopolitan culture of Los Angeles, her family upbringing, and her comprehensive education altogether produced a remarkable result.She grew up as a multifaceted person showing her many talents in a variety of professions such as recording her father's 1970s hit "I Think I Love You" and singing in VH1's TV special Bubblegum Babylon (2002), writing her own songs, modeling for Abercrombie and Fitch and Guess?'s Rock and Republic clothing lines in 2004, and acting.However, she was publicly criticized by her father who would have liked for her to wait before she covered his classic hit.Katie Cassidy was born Katherine Evelyn Cassidy on November 25, 1986, in Los Angeles, California.
Her father, David Cassidy, was a pop star in the 1970s.Her mother, Sherry Williams, was a high fashion model in the early 1970's.Sherry left her career to concentrate on raising her 3 daughters, with husband, Richard Benedon M. Her famous relatives include uncles Shaun Cassidy, Patrick Cassidy and Ryan Cassidy, and grandparents Jack Cassidy, Evelyn Ward and Shirley Jones.During her stint with Artemis Records, she was introduced to the popular boy band Dream Street.There she met Greg Raposo, who wrote the song "We're In Love" for her when they dated in 2002.She also met her ex-boyfriend, Jesse Mc Cartney, there and later appeared as his love interest in his video hit "She's No You".