Happy Days
star Erin Moran has died at the age of 56, TMZ reports.

Moran was found Saturday by police in Indiana after someone called in about an unresponsive female. When authorities arrived, she was already dead. An autopsy is pending.

The actress shot to stardom at age 13 after playing Joanie Cunningham, daughter of Howard (Tom Bosley) and Marion Cunningham (Marion Ross) and sister to Richie Cunningham (Ron Howard), on the hit ABC series Happy Days, which ran from 1974 to 1984. Moran would also star in the Happy Days spin-off Joanie Loves Chachi opposite Scott Baio, which lasted two seasons on ABC. After the show's cancellation in 1983, she returned to Happy Days for its final season.

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Moran's credits also include The Love Boat, Murder, She Wrote and Diagnosis: Murder. Later in life, Moran also appeared on VH1's Celebrity Fit Club.

Following her role on Happy Days, Moran battled alcoholism and eventually moved into a trailer park in Indiana with her husband Steve Fleischmann.

Howard and fellow Happy Days star Henry Winkler paid tribute to Moran on Twitter Saturday night.