Every royal's must-have guide to the holidaysA princess always knows how to celebrate the holidays. There's Christmas, Hanukkah, Yule, Chinese New Year, Saturnalia . . . to name just a few. Then there's gift giving, the royal Genovian Fabergé Advent calendar, hot chocolate with marshmallows—oh, and all those fabulous holiday movies. How will you celebrate this holiday season? Mia and her subjects have a few ideas.