Watch Justin Bieber Rewrite National Anthem For Christina Aguilera!

Justin Bieber can sympathize with Christina Aguilera's experience of forgetting the words to the National Anthem. So the "Baby" singer rewrote the song to make it a little easier to remember!

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Justin admitted he once had to sing "Hark the Herald Angels Sing" the first time he met President Barack Obama and "had no clue what the words were."

So when Justin watched the Super Bowl and saw Christina's performance of the National Anthem he could sympathize.

"For me it's like I don't know the American National Anthem because I'm Canadian," he explained to George Lopez on Lopez Tonight and then sang a bit of "O Canada!"

To help Christina out, he then rewrote the American National Anthem with some of his "Baby" song mixed in to make it easier!

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