Authorities in Indiana found her body Saturday afternoon after getting a 911 call at 4:07 p.m. for "an unresponsive female," the Harrison County Sheriff's Department said.
"Upon the arrival, it was determined that the female was Erin Marie Moran-Fleischmann. First responders determined that she was deceased and an autopsy is pending," the department said.
Moran was cast as Joanie Cunningham, the younger sister of Richie Cunningham, who was played by Ron Howard, a child actor who is now a famed director.
The show aired from 1974 to 1984. It was set in 1950s Milwaukee and was a big hit with a catchy theme song and memorable characters such as The Fonz, played by Henry Winkler.
Moran played the same character in the early 1980s in "Joanie Loves Chachi," a shortl-ived spin-off with her "Happy Days" co-star Scott Baio continuing his role as Chachi Arcola.
Other "Happy Days" spin-offs were "Laverne & Shirley" and "Mork & Mindy."
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