High Quality Content by WIKIPEDIA articles! A changeling is a creature found in Western European folklore and folk religion. It is typically described as being the offspring of a fairy, troll, elf or other legendary creature that has been secretly left in the place of a human child. Sometimes the term is also used to refer to the child who was taken. The apparent changeling could also be a stock or fetch, an enchanted piece of wood that would soon appear to grow sick and die. The theme of the swapped child is common among medieval literature and reflects concern over infants afflicted by as-then unknown diseases, disorders, or mental retardation.