LOUISVILLE, Ky. (WDRB) -- Cancer was the likely cause of death for former child star Erin Moran. 

The Harrison County, Indiana Sheriff's office says the autopsy results show she died of stage 4 cancer.  In a release, they also said no illegal drugs were found in her home in New Salisbury, Indiana. But standard toxicology tests are being performed.

Moran was found unresponsive Saturday, after authorities received a 911 call. Moran had endured numerous struggles in recent years.

Moran was already a veteran actress when in 1974 she was cast in "Happy Days" as Joanie, the kid sister to Ron Howard's Richie Cunningham in the sitcom set in the 1950s. She would later appear with Scott Baio in the "Happy Days" spinoff "Joanie Loves Chachi."

Her more recent credits included "The Love Boat" and "Murder, She Wrote," but she never approached the success of "Happy Days" and was more often in the news for her numerous personal and financial struggles and was reportedly homeless at times.

Her "Happy Days" co-stars remembered her on social media. "Such sad sad news. RIP Erin," Howard tweeted Saturday. "I'll always choose to remember you on our show making scenes better, getting laughs and lighting up TV screens."

"OH Erin... now you will finally have the peace you wanted so badly here on earth," Henry Winkler tweeted Saturday. "Rest In It serenely now.. too soon."

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