 Alexander was born in Newark, New Jersey, the son of Jewish parents Ruth Minnie (née Simon), a nurse and health care administrator, and Alexander B. Greenspan, an accounting manager whose first name Jay later borrowed to create his stage name.He has a half-sister, Karen Van Horne, and a half-brother, Michael Greenspan.Alexander grew up in Livingston, New Jersey, and is a 1977 graduate of Livingston High School.