Mariclare Catherine Costello (February 3, 1936 – April 17, 2026) was an American actress. She was a lifetime member of The Actors Studio. Costello's most notable role was that of Rosemary Hunter Fordwick on the television series The Waltons, from 1972 to 1977. In 1977, after her role on The Waltons, she played matriarch Maggie Fitzpatrick on the short-lived drama show The Fitzpatricks.
Early years Costello was born in Peoria, Illinois, on February 3, 1936, the daughter of Dallas and Margaret Costello. She was named outstanding Catholic actress of the year while she was an undergraduate at Clarke College. She also was awarded during her years in Catholic University's Graduate School of Drama. Her Clarke education included a semester at the University of Vienna in addition to tours of European countries.
Career Costello appeared in the off-Broadway play The Hostage. Her Broadway credits included After The Fall (1964), But For Whom Charlie (1964), The Changeling (1964), Tartuffe (1965), Danton's Death (1965), The Country Wife (1965), Lovers and Other Strangers (1968), A Patriot for Me (1969), and Harvey (1970).
She portrayed a hippie-vampire in the 1971 cult horror film Let's Scare Jessica to Death.
After her acting career, she was an acting professor at Loyola Marymount University in Los Angeles.
Personal life and death Costello was married to actor Allan Arbus until his death in 2013. The couple had one child. She died in Brooklyn, New York on April 17, 2026, at the age of 90.
Filmography Year Title Role Notes1967 The Tiger Makes Out Rosi 1969 N.Y.P.D. Eloise Hendrix S2.E16 - "The Attacker"1970 Pound Honky Killer's Wife 1970 Storefront Lawyers Nancy Collins S1.E3 - "Murph Collins vs. Tomorrow"1971 Let's Scare Jessica to Death Emily/Abigail 1972 Ironside Mary Ellen Wells S6.E2 - "The Savage Sentry"1972–77 The Waltons Rosemary Hunter/Fordwick 15 episodes1974 Kojak Diane Gordon S1.E13 - "Death Is Not a Passing Grade"1974 After the Fall Louise TV film based on Arthur Miller's play by the same name1974 The Execution of Private Slovik Private Slovik's wife Antoinette NBC TV film1974 The Gun Beryl Strauss ABC Movie of the Week1975 Barnaby Jones Ruth Granger S3.E21 - "The Deadlier Species"1975 Harry O Emily Weston S1.E15 - "For the Love of Money"1977 This Is the Life Ann Episode: "Stranger at the Door"1977 Raid on Entebbe Gabrielle Krieger 1977–78 The Fitzpatricks Maggie Fitzpatrick 13 episodes - regular cast1979 The Incredible Hulk Kay Wallace S2.E18 - "No Escape"1979–81 Lou Grant Maxine Kintner/Louise Larsen 2 episodes1980 Ordinary People Audrey Butler 1980 Little House on the Prairie (1974 TV series) Helen Crane 1981 Ragtime Emma Goldman (workprint edit only)1981 Coward of the County Emma Television Movie1982 Hart to Hart Anita Boyer S3.E18 - "Deep in the Hart of Dixieland"1982 Fame Mrs. Mendenhall S3.E9 - "Secrets"1983 Nightmares Adele Cooney (segment "The Bishop of Battle")1984 The Adventures of Buckaroo Banzai Across the 8th Dimension Senator Cunningham 1984 Victims for Victims: The Theresa Saldana Story Jane Bladow NBC TV film1985 Heart of a Champion: The Ray Mancini Story Ellen Mancini CBS TV film1986 Murder, She Wrote Cassie Latham Burns S2.E15 - "Powder Keg"1990 In the Heat of the Night Darlene S3.E14 - "December Days"1990 Santa Barbara Sister Lillian 2 episodes1993 Indecent Proposal David's Mother 1997 High Tide S3.E21 - "Ghost Story"1998 Chicago Hope Mother Mary Catherine S4.E13 - "Memento Mori"1999 Judging Amy Dr. Singer S1.E7 - "An Impartial Bias"2002 Providence Helen Norris S4.E21 - "Smoke and Mirrors"2011 Assisted Loving (video short) Pearl
References
External links Remembering Jessica: An Interview with Mariclare Costello - July 2011