Family
- father Stephen Parker: Divorced from Parker's mother
- mother Barbara Forste: Divorced from Parker's father; married second husband Paul Forste in 1969 and they had four children together
- step-father Paul Forste: Married Parker's mother in 1969; father of Parker's four step siblings
- brother Pippin Parker: Born in 1961; member of Naked Angels theater group
- brother Timothy Britten Parker: Born in 1962; appeared with sister on Broadway in "The Innocents" (1976); member of Naked Angels theater group; featured in the original production of the musical "Rent" (1996)
- sister Rachel Parker: Born c. 1963
- half-brother Andrew Forste: Younger; son of Barbara and Paul Forste
- half-sister Megan Forste: Younger; daughter of Barbara and Paul Forste
- half-sister Alegra Forste: Younger; daughter of Barbara and Paul Forste
- half-brother Aaron Forste: Younger; son of Barbara and Paul Forste
- son James Wilkie Broderick: Born Oct. 28, 2002; father Matthew Broderick
- daughter Marion Loretta Elwell Broderick: Twin of Tabitha; born June 22, 2009 by way of a surrogate
- daughter Tabitha Hodge Broderick: Twin of Marion; born June 22, 2009 by way of a surrogate
Companions
- Companion Joshua Kadison: Dated in the early 1990s; he described their tumultuous relationship and their cat Moses in the song "Jessie" on the album Painted Desert Serenade
- John F Kennedy: dated briefly
- Nicolas Cage: had one-year relationship c. 1991
- Robert Downey: while filming "Firstborn" (1984); together from c. 1984 until they separated in August 1991
