Spanish children receive their gifts the 6th of January by the Three Kings (Melchior, Gaspar and Balthazar). We call them los Reyes Magos or los Magos (the Magi or the Three Wise Men).
But this day will not be completed without a ‘roscón de Reyes’ (King cake). The Spanish King cake or ‘roscón’ is a yeast-based brioche made in the shape of a ring and filled with almonds and dried fruits. A trinket is placed in the cake. The person who gets the trinket on his/her piece of cake (usually the youngest member in the family) becomes the king/queen for the day. For more information see Wikipedia entry for King cake HERE.