“Even when we were kids, the term ‘child actor’ was shorthand for ‘future f---ed up adult,’” wrote actor Clint Howard, the rare child star to become a fully functioning adult, in his memoir The Boys, written with his brother, the equally productive director Ron. “Then as now, Hollywood is littered with cautionary tales.” The Howard siblings notwithstanding, a cursory glance at the history of show business reveals countless performers who charmed audiences as youths, fell into irrelevance as young adults, and drifted into disrepute, scandal, or otherwise sad outcomes.