Edit: something happened to the video but now it’s fixed.
Yes, I am aware that the historical Jesus was most likely born in the Springtime. Stop being a Grinch.
When I was in college, I had a job working as a church musician. I eventually worked my way up to Music Minister. Every year we had an evening service on Christmas Eve. At the end, everybody would have lit candles, the lights would be turned off, and we would sing Silent Night. After the first year, I remembered to have my own light on the piano so I could see the music! Things evolved over time. I started bringing frankincense and myrrh incense from a curiosity shop near my home owned by this guy. And I don’t know whose idea it was, but the last few years I was there after Silent Night we would sing Happy Birthday to Jesus and have a birthday cake.