Here's a fun fact: Babies born the year Mariah Carey first released "All I Want For Christmas Is You" are now old enough to order a round of kamikaze shots. Some things never change, though. More than 22 years later, Carey is still merrily belting out the festive tune for anyone who asks. This time, it's James Corden who's asking. Though he's no doubt at risk of getting vehicle-induced bed sores from all that driving around, the Late Late Show host couldn't resist inviting Carey over for a holiday-themed edition of "Carpool Karaoke." You'll never guess which song they sang. But wait! There's a twist! Corden has been asking other pop stars to sing "All I Want For Christmas Is You" this whole time. Cut to past "Carpool Karaoke" guests like Adele, Demi Lovato and Nick Jonas, Elton John, Selena Gomez, Lady Gaga, Gwen Stefani, Chris Martin, and (yes, yes, yes) the hilariously enthusiastic Red Hot Chili Peppers all lending their vocals to the holiday hit. Observation: Flea is the ultimate elf, no? This might be the best present we get this year. Quit while you're ahead, Santa.