Jesse McCartney & Anne Hathaway

Pop singer and actor Jesse McCartney was a child performer dynamo, singing on Broadway and landing an acting gig on All My Children before even joining his first boy band, a feat that came at the age of 12. Teen poppers Dream Street scored a platinum album with their self-titled debut before spinning off the careers of Chris Trousdale and McCartney himself, who started contributing music to children's films like Cinderella Story ("The Best Day of My Life"), Stuck in the Suburbs ("Good Life"), and Ella Enchanted, for which he performed a version of Elton John's "Don't Go Breaki...