Nancy Ann Rosher, first appearing as Dorthy Rosher and ultimately Joan Marsh, was born July 10, 1913. She was the daughter of Charles Rosher, the first cinematographer to win an Academy Award for Best Cinematographer in "Sunrise: A Song of Two Humans". Because of her father's profession she found herself in 15 films (mostly uncredited) by the time she was eight, several starring Mary Pickford. These include The Little Princess (1917), Daddy-Long-Legs (1919), and Pollyanna (1920).

After some formal schooling, Joan returned to the screen. In the 1930's Joan had supporting roles in a number of films whose headliners were Garbo, Crawford, and Loretta Young. Some critics believed she stole Three Girls Lost (1931) from Young. She had a couple female lead roles, Maker of Men (1931) and High Gear (1933), but often was cast as the pretty, but second or third featured actress. In fact, some have conjectured that her good looks kept people and critics from appreciating her certainly credible acting ability.

In the late 30's and early 40's she made a comeback of sorts, but the roles were in films you won't find on the AFI list. These included one of the best Chan outings, Charlie Chan on Broadway (1937) where she met and married the film's screenwriter Charles Belden, and a well made Republic serial, The Secret Service in Darkest Africa (1943). The last two of her 68 films were Bowery Boys vehicles, clearly an indication it was time to retire. Joan had a successful small business career after retiring from films. She died in Ojai Ca. on August 10, 2000.