The Waltons’ Star Mariclare Costello Dies at 90 💔

Mariclare Costello, the veteran actress best known for playing Rosemary Hunter on The Waltons, has died at the age of 90.

Costello passed away on April 17, 2026, in Brooklyn, New York.

Her career stretched across decades and included memorable work on Broadway, television and film. She was a lifetime member of the Actors Studio and performed alongside legendary names including James Earl Jones, Faye Dunaway and Jimmy Stewart.

Fans may remember her from The Waltons, as well as films such as Ordinary People and The Adventures of Buckaroo Banzai Across the 8th Dimension. She also appeared in television favorites including Kojak, Lou Grant, Murder, She Wrote, Chicago Hope and Judging Amy.

Beyond acting, Costello devoted much of her later life to teaching and directing, helping inspire young performers through drama programs and community organizations.

She was also married to actor Allan Arbus, known for his role as Dr. Sidney Freedman on MASH*, until his death in 2013.

Mariclare Costello leaves behind a remarkable legacy on stage, television and film—and countless memories for the audiences who watched her work.

🕊️ Rest in peace, Mariclare.