A figure of childhood folklore said to visit secretly after…

A figure of childhood folklore said to visit secretly after a child loses one of its milk teeth. The little one places the lost item under the pillow, and by morning it has been swapped for a coin or banknote. The custom spread widely in the United States during the twentieth century. In France and Spanish-speaking countries, a small mouse traditionally performs the same role, called Ratoncito Pérez in Spain.

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