Erin Moran, Who Played Joanie on ‘Happy Days,’ Dies at 56

Erin Moran, the former child actor who played the sweet but mischievous Joanie on the television series “Happy Days” and “Joanie Loves Chachi,” has died. She was 56.

The Harrison County Sheriff’s Department in southern Indiana confirmed her death. She was found unresponsive on Saturday afternoon, and the authorities said an autopsy was pending.

Ms. Moran started acting as a child at 5, and got her first taste of television in a commercial for First Federal Bank. She went on to play minor characters in television and film in the late 1960s and early ’70s. At age 12, she landed her biggest role: Joanie, the freckle-faced troublemaker and sister of Richie Cunningham, the all-American teenager played by Ron Howard.

Over the 10-year run of “Happy Days,” Joanie transformed from the young teenager who complained about being sent to her room to a major character on the show. In later seasons, Joanie’s love interest with the aspiring musician Chachi Arcola became a major story line.

In 1982, the two characters were given their own show, “Joanie Loves Chachi,” a widely panned comedy that followed their romantic adventures and musical pursuits in Chicago. While “Happy Days” was a No. 1 hit, the spinoff with Ms. Moran and Scott Baio, who played Chachi, lasted only 17 episodes.