"My Heart Will Go On" wasn't the only song Céline Dion sang at the 2017 Billboard Music Awards.

The Canadian powerhouse took the stage to perform a breathtaking, chills-inducing rendition of the Titanic theme song, in honor of the film's 20th anniversary. But shortly after Dion left the stage, she couldn't help but burst into song once more — but this time, she was singing along to Cher's performance of "Believe."

Dion was stopped dead in her tracks backstage by Cher — who ruled the BBMAs stage by belting out her 1998 dance-pop hit "Believe," wearing nothing but heart-shaped pasties, a thong, and a "robe" made out of strands of silver jewels (just further proving her ICON award was well-deserved). As is reasonable, Dion danced and sang along to the 71-year-old's showstopping performance, leading the press room in an impromptu karaoke session.

Several people captured the legendary moment on video (bless you, social media). Naturally, the clips prove that Dion's vocal range is just as impressive in a random sing-along session as it is in a full-blown Vegas production. Watch below:

Even Céline Dion can't help but fan-girl over Cher. But can you blame her?

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