Katy Perry was happy to perform one of her early songs with Elmo from 'Sesame Street,' but some parents weren't enthused.

Cumulus the Cockatoo is a huge fan of the show, especially when it comes to beloved Elmo. In fact, when Elmo's song comes on, he can't help but shake his tail feather!

Turns out, that song is “Elmo’s Song,” and the two dueted on a pop rendition that featured the Not-Too-Late Show ‘s house band and a healthy dose of Auto-Tune on Nas’ vocals.

Watch a duet between Elmo and Hoots the Owl on stage with the Jazz at Lincoln Center Orchestra with Wynton Marsalis. Be careful not to sprain yourself smiling.

After playing two sold-out shows at Madison Square Garden, Stapleton stopped by 123 Sesame Street to sing with Elmo and friends ...

In their interview with AP, Elmo and Abby Cadabby said the Count always talks about Loretta Lynn. Elmo said Stapleton's song about the power of music was really great.

Loretta Lynn, meanwhile, joined for a math lesson with the Count on the song, “Count on Me.” In their interview with AP, Elmo and Abby Cadabby said the Count always talks about Loretta Lynn. Elmo said ...