By Courtney E. Smith

The GRAMMYs and CBS are throwing quite a Christmas bash—and now Sam Smith and Big Sean will join the party.

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A Very GRAMMY Christmas, at which a lineup including Pharrell Williams, Maroon 5, Ariana Grande, Mary J. Blige and Tim McGraw, will perform holiday favorites and current hits, has added these two performers in different capacities. Smith will perform on his own, while Sean has been added to Grande’s performance.

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Additionally, the GRAMMYs announced its plans for revealing the nominees this year. The first four categories will be announced starting at 8:30 a.m. ET on CBS This Morning. From 9 a.m. to 2 p.m. ET nominations will be revealed on Twitter in video posts by a series of artists, and then be posted on the GRAMMYs website.

The Album of the Year nominees will be made public that evening during the GRAMMY Christmas telecast.

A Very GRAMMY Christmas airs on CBS on Dec. 5 at 9 p.m. ET.

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