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Mariah Carey Sends Flowers To Brenda Lee ... Congrats On #1 Christmas Hit 65 Years Later!!!

Mariah Carey might be the queen of Christmas, but she's still a good sport ... sending Brenda Lee flowers after the singer topped the chats with her holiday hit, 65 years after it was recorded.

Brenda, known for her classic Christmas track, "Rockin' Around the Christmas Tree," shared Mariah's gesture on Instagram Thursday, showing off a bouquet with a handwritten note from Mariah -- one that wishes her a Merry Christmas and a big congrats for her "historic #1."

As we reported, Brenda's holiday tune became a star on the top of Billboard's Hot 100 list Monday -- the first time it's had the honor since its release back in 1958. Shockingly, Brenda was only 13 when she recorded the hit.

The song has been creeping its way up to the top in recent years ... and the 78-year-old singer finally put out a long-overdue music video for the song last month.

She also sang her track while taking to the skies -- much to the delight of her fellow airplane passengers!

As you know, Mariah's "All I Want For Christmas Is You" often dominates every holiday season ... but it looks like she's got no problem sharing the stage this year.

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