Williams died of a “brief illness” in Los Angeles on January 25, according to a statement released by her children, Zak and Emily Hudson.

“The passing of our kind, hilarious mother, Cindy Williams, has brought us insurmountable sadness that could never truly be expressed,” the statement reads, per AP. “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.”

NORTHERN CALIFORNIA – 1973: Ron Howard and Cindy Williams as high school sweethearts in a scene from the Universal City Studios production of “American Graffiti” in 1973 in Northern California. (Photo by Michael Ochs Archive/Getty Images)

Born in Los Angeles on August 22, 1947, Williams’ career began with TV roles in shows like Nanny and the Professor and Love, American Style.

Before catapulting into stardom, she was a theater student alongside Sally Field.

She then broke out with roles in two of the most acclaimed Hollywood films of the 1970s: she played Laurie Henderson in George Lucas’ American Graffiti, the high school sweetheart of Ron Howard’s character, and also had a role in Francis Ford Coppola’s The Conversation.

But it was another TV appearance that would lead to her most famous role. Williams was cast as a guest star in an episode of Happy Days, along with actress Penny Marshall, as a pair of dates for Richie and Fonzie named Laverne and Shirley.

The appearance was so successful that producer Garry Marshall created a spin-off series, Laverne & Shirley. The show was became very popular, running for eight seasons, becoming America’s most-watched show in its third season.

Kicking off each week with one of TV’s most memorable intros (“One, Two, Three, Four, Five, Six, Seven, Eight! Schlemiel! Schlimazel! Hasenpfeffer Incorporated!”) the show, set in the late 1950s through the mid ’60s, followed the adventures of Laverne DeFazio (Marshall) and Shirley Feeney (Williams), best friends and roommates.