Mariclare Costello, a veteran stage and screen actress known for The Waltons and Let’s Scare Jessica to Death, died April 17, 2026, in Brooklyn at 90.
Born in 1936 in Illinois, she studied theater and later built a strong career in New York, performing with major institutions and alongside stars like James Earl Jones and Faye Dunaway. She appeared on Broadway and in works by Arthur Miller.
On screen, she was known for her role as Rosemary Hunter in The Waltons and appeared in numerous TV shows and films, including Ordinary People.
She was married to Allan Arbus until his death in 2013. Later in life, she focused on teaching and directing, mentoring young actors in Los Angeles.