Now that we are in the full swing of the Christmas season, you're probably getting your fill of Christmas music. (If you're not over-filled on Christmas music and want some more helpings, our friends over at K103 are playing all your favorite holiday tunes 24 hours a day.) One of the big songs this year is Mariah Carey's "All I Want for Christmas Is You." And in honor of the season, Jimmy Fallon and his house band, The Roots, pulled together another of their famous covers using kiddie instruments. Joined by Carey and a group of cute little scamps, Fallon has provided us with our favorite version of this song.