If kids are there, one is supposed to go under the table and choose who gets what slice. If one receives the figurine, they become the king/queen for the day.
http://www.livinglanguage.com/blog/2012/12/27/la-galette-des-rois-celebrating-the-feast-of-the-epiphany-in-france/
https://frenchmoments.eu/epiphany-in-france-lepiphanie-en-france/
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