Mary Kay Bergman (June 5, 1961 – November 11, 1999), initially credited on South Park as Shannen Cassidy, was an American voice actress and voice-over teacher.
Born in Los Angeles, California, U.S., she had an interest in fantasy and animation early in her life. She acted in plays in high school and also studied theater at University of California, Los Angeles. After unsuccessful acting jobs, she was considering a career in the Air Force, when "going wild" on karaoke at a housewarming party changed her life.
In 1989, she began voicing the Disney character Snow White. Bergman is widely known for her voice work in the earliest seasons of South Park and The Fairly OddParents. She did voice work for over 400 television commercials and voiced over 100 cartoon, film and video game characters throughout her career.
Bergman was married to voice actor Dino Andrade. Bergman committed suicide in November 1999. Shortly after her death, Andrade established the Mary Kay Bergman Memorial Fund.