Stan nearly ruins Steve's birthday party by demanding that Steve act his own age, but Francine saves the day by getting the moonbounce Steve has always wanted. When Stan reluctantly joins in the fun, he comes to realize he never had the chance to be a kid. When Stan has a run-in with local law enforcement, the father-son roles are reversed, forcing Steve to become the man of the house. Meanwhile, Klaus tries to re-capture the feeling of having a human body by getting a haircut.

When Hayley goes to a My Morning Jacket concert against Stan's wishes, he crashes the show to bring her back home, but when he hears their music for the first time, it calls to him and he's smitten. Stan becomes obsessed with the band and decides to follow them on the road as a groupie.