December Festivals (Other Than Christmas) - December Theme Month

I Should Have Known is celebrating all month long! Our theme for December is... December! Kicking off the festivities is Quizmaster Sups, who discovered four festivals which are celebrated in December. Except we're late to the party for one of them! See if you can figure out which holiday festival doesn't actually happen in the twelfth month along with hosts Andi and Tanner!