Katherine Marie Heigl is an American actress with an estimated net worth of $18 million. Born in Washington, D. C. on November 24, 1978, she is best known for her recurring role as Dr. Izzie Stevens on the hit TV drama, "Gray's Anatomy." Heigl got her start as a child model with the world-famous Wilhemina Modeling Agency. Her film debut came when she appeared in the movie, "That Night." She has also appeared in several other films, including "Knocked Up," "27 Dresses" and "The Ugly Truth." Katherine Heigl is considered a national and international sex symbol and, as such, has appeared on the covers of many magazines, including Maxim, Cosmopolitan and Vanity Fair. An avowed feminist, she works hard for women's causes and for animal welfare, too. She remains a busy and in-demand TV and movie actress.