Grey's Anatomy: Grandma Got Run Over by a Reindeer

The gang helps Alex pass his boards practical exam so that he can stay on at the hospital, an act of generosity that irks Izzie. Meanwhile, a little boy needs a new heart, but turns down the one that is ready for him. Cristina and Burke have opposing views on how to handle his case. Meanwhile, George tries to keep a woman's entourage away from her, as they are giving her an ulcer, while a sour Derek fails to fall in line with Addison's Christmas cheer.