Madio was born as one of seven children in his family. At the age of 15, he had his first audition in Steven Spielberg's 1991 film Hook. He landed the role of "Don't Ask", one of the Lost Boys. Among the cast of Hook was Academy Award winner Dustin Hoffman, who had been cast as the villainous Captain Hook. Hoffman took notice of Madio and had him cast as his character's son in the 1992 comedy Hero.