When you watch Alli Simpson's new music video with Jack & Jack for their song "Roll 'Em Up," you'll understand while we're obsessed. The catchy tune features the Mudd Jeans campaign co-stars cruising through SoCol, hitting up a dinner (the same one where Bella Thorne shot "Call It Whatever"), and dancing like crazy. But want to know something even more shocking? This tune was actually written by Selena Gomez and Cody Simpson — and was originally meant as a duet for them.

"It is the same song [that Cody and Selena were working on], but now it’s called ‘Roll Em Up.’ It’s featuring Jack and Jack, and we’re out in the Valley right now shooting in a very cool old school diner, and I’m very excited about it," she EXCLUSIVELY told us while she was filming the music video.

CLICK HERE FOR SONGS YOU DIDN’T KNOW WERE WRITTEN BY OTHER ARTISTS!

The radio show host also says that if her older bro and her bestie actually did make a video for the song, it would probably be pretty similar to her one with Jack & Jack!

"I think if [Selena and Cody] did the video, the vibes would’ve been very similar. It’s still got that old school feel. So I don’t think it would’ve been too much different because they dealt with treatment as well and coming up with the idea so I think if they did it, it would’ve been the same, but them!"

However, we definitely like the unique spin that Alli and Jack & Jack put on the song and their vid! It's full of spunk, and totally them.

What do you think about "Roll 'Em Up"? Are you surprised that Selena and Cody wrote it? Let us know in the comments!

Reporting credit: Morgan McMurrin

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