Cara was scheduled to film scenes in London for the festive track, which was originally released in 1973.
The video will feature the Rocket Man legend, now 77, playing the piano in his Seventies pomp before he morphs into his friend Cara.
A source said: “It’s a really fun concept and Cara jumped on the idea when it was first put to her.
“Original footage of Elton from the first video playing and singing at his piano will be used.
“Then Cara will be seen as Elton, dancing and messing around behind the scenes.”
Cara has been at a number of Sir Elton’s concerts over the years, including his epic Glastonbury gig last year — the final UK show of his farewell tour.
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Cara stunned in the Christmas themed snapsCredit: michaelbaileygates.
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The model in the snowy Calvin Klein campaignCredit: michaelbaileygates.