Opera with a Christmas connection was not that easy to find, and I must confess this is a new one on me.
Amahl and the Night Visitors is an opera in one act by Gian Carlo Menotti. It was commissioned by NBC and first performed by the NBC Opera Theatre on December 24, 1951. It was the first opera specifically composed for television in America. From 1951 until 1966 it was presented every year on NBC. It might be better known to US forum members.
The plot revolves around the three Kings who stop at the home of a poor mother and her disabled son for rest on their way to find the baby Christ. Anyway here was my favourite bit, where the Kings asking about the baby Christ are answered by the mother's referring to her son.