Fans of Bridgit Mendler already know she's a terrific singer. After all, the star of the Disney Channel original series "Good Luck Charlie" sings the show's theme song, and has sung in lead roles of Disney original films like "Lemonade Mouth." But she's no newcomer. Bridgit has been writing songs since age 6, and in recent years has made songwriting a daily habit. All that discipline paid off because, with her debut Hollywood Records album nearly done and a premiere single set to drop, Bridgit Mendler is about to rock the world with her vocal talent.