Somerville died at her home in New York City on Thursday.
Rest in peace, Phyllis Somerville. The actress died of natural causes at her home in New York City on Thursday, her rep tells ET. She was 76.
"She was the consummate professional who lived her dream of being a working actress her entire life in NYC which spanned over 45 years," Somerville's manager of over 28 years, Paul Hilepo, tells ET. "I will miss her greatly. Her friends and colleagues will miss her greatly as well."
Somerville was perhaps best known to fans as the character Marlene in The Big C. The Iowa-born actress began her acting career at age 9 in 1952, appearing in an episode of the TV series Guiding Light. Over the next few decades, she also had roles on Law & Order, NYPD Blue, Sex and the City and The Sopranos.
The actress also appeared in movies like Swimfan, Stoker and The Curious Case of Benjamin Button, as well as on Broadway. Somerville played Mrs. Henry DuBose in the stage production of To Kill a Mockingbird and appeared as Mrs. Chasen in Once in a Lifetime.
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