It's Christmas time and there's excitement galore at the house of the boy with red pants! All the family is there to celebrate ... but something isn't right. It's his bum of course! It's too plain so he wants to zing it and bling it! He imagines all the ways he could decorate it. He settles on a Christmas tree bum -- it's a truly stunning thing! Then again, is having the most decorated bum the most important thing at Christmas time?