Busy Wheeler, a spirited tomboy who's adopted and best friends with a mentally handicapped boy named Billy, is suddenly having strange feelings for the new girl at school and fighting an overwhelming sensation that she's growing up too fast. After getting into trouble too many times at school, she is sent away to live for the entire summer with an aunt she's never met. As the summer unfolds, so does a deep-seated family secret, and Busy comes face to face with her birth mother. With the help of a new friend, Busy must learn to swallow her pride and make amends with a mother she's never known while laughter, unexpected kisses and a continuous trail of mischief lead her on an endless journey of adolescent discoveries.