Demi Lovato performed at the Super Bowl a decade after tweeting about it

Demi Lovato had big plans to sing at the Super Bowl, ten years ago. 

Lovato's powerful rendition of the national anthem kicked off the country's most popular sporting event of the year on Sunday. Her performance made such an impact, some praised it as "the best since Whitney Houston." 

It wasn't new to Lovato, though, who...