Sullivan is the daughter of actor Barry Sullivan. Her first feature film was The Angry Breed (1968). Other film appearances include Plaza Suite (1971), The Other (1972), The Candidate (1972), Getting Straight (1970), Breakfast in Bed (1978) and Shadow of Doubt (1998).
Sullivan wrote the play J for J (Journals for John) which was prompted after she found a packet of unsent letters (in 1995) written by her father decades earlier to her older brother, Johnny, who was mentally disabled. The play premiered on October 20, 2001. John Ritter, who in real life had a handicapped brother, played Johnny, Sullivan played herself, and Jeff Kober portrayed her father Barry.
