Los Angeles, California - It's a sad day for sitcom aficionados, as the family of Happy Days and Laverne & Shirley star Cindy Williams announced her death at the age of 75.

A statement cited by CNN early on Tuesday said: "The passing of our kind, hilarious mother, Cindy Williams, has brought us insurmountable sadness that could never truly be expressed."

Williams reportedly died in Los Angeles after suffering through a short illness.

She was best known for her role as Shirley Feeney, first on the classic show Happy Days, then in her own spinoff, Laverne & Shirley, alongside the late Penny Marshall, who died in 2018, also at 75. The latter series ran for five seasons from 1976 to 1983 and quickly became a hit, garnering her a Golden Globes nomination for best actress.

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Williams also had a successful film career, the highlight of which was her appearance in the George Lucas' acclaimed 1973 movie American Graffiti.

"Knowing and loving her has been our joy and privilege. She was one of a kind, beautiful, generous and possessed a brilliant sense of humor and a glittering spirit that everyone loved," the statement released by her children with musician Bill Hudson, Zak and Emily, continued.

Henry Winkler, who played Fonzie in Happy Days, also paid tribute to Williams, calling her "a fine and talented human being."