WIKIPEDIA:

“ Cass Elliot (September 19, 1941 – July 29, 1974), born Ellen Naomi Cohen and also known as Mama Cass, was an American singer and member of The Mamas & the Papas. After the group broke up, she released five solo albums. In 1998, Elliot, John Phillips, Denny Doherty, and Michelle Phillips were inducted into the Rock and Roll Hall of Fame for their work as The Mamas & the Papas.

Early life and career
Ellen Cohen was born to Philip and Bess Cohen in Baltimore, Maryland, where she grew up. The family then moved to Alexandria, Virginia (a suburb of Washington, D.C.). She adopted the name "Cass" in high school—possibly, as Denny Doherty tells it, borrowing it from the actress Peggy Cass—but in any case, it was "Cass", not "Cassandra." She assumed the surname Elliot sometime later, in memory of a friend who had died.
While still attending George Washington High School, she became interested in acting and was cast in a school production of the play The Boy Friend. She left high school shortly before graduation and relocated to New York City to further her acting career, and toured in the musical The Music Man, but lost the part of Miss [......] ”

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