2.12 Grandma Got Run Over By a Reindeer

A young boy needs a heart transplant but doesn't seem to want it, and an argument over his treatment exposes major philosophical differences between Burke and Cristina. Meanwhile, when the interns rally to help Alex prepare to re-take his exam, Izzie feels betrayed and Meredith has to remind her of the true spirit of the Christmas holiday. Derek performs brain surgery on the patriarch of a mixed Jewish/Christian family who discuss celebrating Chrismukkah, but isn't in a festive mood despite a reconciliation with his wife.