VIDEO: Demi Lovato's Death Metal "Barney" Theme

As most of her fans know, singer Demi Lovato got her start as a youngster on the kids show Barney. So when Demi popped by the Late Night with Jimmy Fallon studio on Thursday night to promote her album, Here We Go Again, her new BFF Jimmy convinced to rock out to a death-metal-ified version of that show's well-known theme song.

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