Lizzie McGuire is a Disney Channel classic, and it's been around for a long time. Although the show went off the air in 2004, the first episode actually premiered on January 12, 2001. Can you believe it?! In honor of the 16-year anniversary of the show, J-14 has uncovered shocking facts about the series.

You'll learn who really sang for Hilary Duff in The Lizzie McGuire Movie (hint: it's a member of her family!), and find out the real reason there was never a sequel to the film. Selena Gomez also could have played a very important role in the franchise, even though it never came to be! Did you know that?

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Watch the full video below to see all the shocking facts about the show. Can you believe it's been 16 years since it premiered on the Disney Channel? Sound off in the comments below!