Mary Martha Byrne (born December 23, 1969) is an American actress, singer and television writer. She played the role of Lily Walsh Snyder on the soap opera As the World Turns from 1985 to 1989, then again from 1993 to 2008; as well as, from 2000 to 2003, Lily's twin sister, Rose D'Angelo. Byrne has also appeared in other stage, television and movie roles, including the title role in the 1983 film Anna to the Infinite Power