Bye Bye Birdie is a 1963 American musical comedy film from Columbia Pictures. It is a film adaptation of the stage production of the same name. The screenplay was adapted from Michael Stewart's book for the musical by Irving Brecher, with music by Charles Strouse and lyrics by Lee Adams. Wikipedia
(after Kim has dyed her hair) Harry McAfee: You dare defy your mother? Kim McAfee: Well, it's my hair. Harry McAfee: Not till you're 21!