I'm the most Kkkrackkkers of Amerikkkans so my tradition is just getting drunk off mulled wine and re-watching bad holiday movies with relatives I only kinda like.
I'm sometimes a little jealous of people who have weirder shit going on, like gremlins who slam doors and steal sausages or shitting Christmas logs. We need to bring back weird ass half-pagan shit.
It's connected to Catholic feast days. More connected to the feast of the Epiphany on January 5th, which my mother's Irish-American family referred to as "Little Christmas." According to my grandaunt, that would mark the time when the family would take down the Christmas tree.
https://en.m.wikipedia.org/wiki/Befana
Removing the decorations on twelfth night is customary in a lot of places.
I did not know that until one year when we took down the tree in a hurry the day after Christmas and my grandaunt was upset because it was contrary to established custom.
The other option is candlemas, but thats usually when you put the tree up on Christmas eve, Advent being technically not Christmas.