(Daniel Boczarski/Getty Images for iHeartMedia)

Niall Horan And Lewis Capaldi Made Our 'Teenage Dream' Come True With A Dazzling Acoustic Cover

… And they hardly even practiced!

With Christmas just days away, it's time for us to face the facts: The iHeartRadio Jingle Ball Tour 2019 is nearing its end. Luckily, the tour isn't coming to a close without a few surprises first. And last night, Niall Horan and Lewis Capaldi took the stage together at Chicago's Allstate Arena for 103.5 KISS FM's Jingle Ball with the most angelic cover of Katy Perry's "Teenage Dream" you've ever heard.

Admittedly nervous, the two began their cover of the hit song by strumming on their acoustic guitars. "We practiced this in the bathroom," Horan explained. "We didn't do a soundcheck, so God knows what happens in the next three minutes." Fortunately, those next three minutes were absolute magic, with Horan and Capaldi splitting the verses and coming together to harmonize on the chorus.

Their duet was special for many reasons. First and foremost, the entire arena joined in, reminding us all that Perry's hit 2010 single about being young and falling in love still hits. Moreover, fans of both Horan and Capaldi know that they're actually very close friends in real life, making their rendition of the song that much more dazzling and heartwarming.

"Niall Horan and Lewis Capaldi's friendship is pure gold," one fan tweeted after watching their performance. "We shall treasure it forever." And loads of other fans on the internet agree. In fact, several people on Twitter requested that the two get in the studio together and record a studio version of their previously unrehearsed, stripped-down cover.

While it's too soon to tell whether a studio version of their cover will ever come to fruition, what we do know is that this won't be the last time we'll be seeing Horan and Capaldi together on the same stage. Not only are they both scheduled to perform tonight (December 20) in Atlanta for Power 96.1's Jingle Ball, but Capaldi is also joining Horan on his Nice To Meet Ya North American tour this coming spring, which kicks off in Nashville on April 20. See you there!