The actress was best known for her work on the TV sit-coms "Benson" and "Soap," as well as on the soap operas "Guiding Light" and "Another World." She also had a recurring role on "Beverly Hills, 90210," and appeared in the movies "Mermaids" and "White Water Summer," E! News noted.
Her Feb. 11 death was confirmed to the Los Angeles Times.
McWilliams was married to "Mr. Mom" and "Johnny Dangerously" actor Michael Keaton from 1982 to 1990. They have one son together, Sean Douglas, E! News said.
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