Why did Jo Van Fleet win an Oscar?

Catherine Josephine Van Fleet was an American stage, film and television actress. During her long career, which spanned over four decades, she often played characters much older than her actual age.

In February 1960, in recognition of her career in the motion picture industry, as well as her work on stage and television, Van Fleet was awarded a star on the Hollywood Walk of Fame.

Why did Jo Van Fleet win an Oscar?

Van Fleet won a Tony Award in 1954 for her performance in the Broadway production, The Trip to Bountiful and the next year, she won an Academy Award for Best Supporting Actress for her supporting role in East of Eden.