So this is funny ... all the "ex" Kardashian men seem to regret breaking up with their respective girlfriends -- Kourtney, Khloe, and Kylie -- so when the holidays roll around, they somehow get back into these ladies' good graces and get an invite to the family's infamous Christmas party and so goes the romantic reunions!

Kourtney and Younes, Khloe and Tristan, Kylie and Travis all reunited at the party and one unlikely guest was there to witness it all -- no, not Quavo, we'd expect him to be there -- ELON MUSK! We'd think he'd be the type to make fun of the Kardashians, not party with them! And his girlfriend Grimes?!! Strange bedfellows, indeed ...

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Christmas Eve 🎄

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