Callaway and her sister, singer and composer Ann Hampton Callaway, sang the theme song for the Fran Drescher comedy series "The Nanny", composed by Hampton Callaway. The Callaway sisters have appeared together in a number of cabaret and stage productions. Recordings of two of them, "Sibling Revelry", recorded live at Rainbow and Stars in 1995 and "Boom!" recorded live at Birdland in 2011, have been released. Liz Callaway is married to former actor and acclaimed director Dan Foster. Foster is one of the three founding producers of the Hudson Stage Company, a nonprofit, professional theatre company in residence at Pace University in Westchester County, New York.