I told him about a particular Christmas at my parent's house. My older sister's husband, who is a very able musician, brought his cello along and, after all the presents were opened and while mom and others were preparing the mid-day meal, he began to play songs of the season for all to enjoy. At one point, dad requested 'O Holy Night' and I believe something was said about it being his favorite. At any rate, I know he liked it very much. And so does his son and grandson.
Groban probably likes it, too, but he's not related.