For our family, we start celebrating the 12 days starting the day after Christmas - which incidentally The 12 days of Christmas is the period in Christian theology that marks the span between the birth of Christ and the coming of the Magi, the three wise men. It begins on December 25 (Christmas) and runs through January 6 (the Epiphany, sometimes also called Three Kings’ Day). You can read more about the old tradition here
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