changeling
n//ˈtʃeɪn(d)ʒlɪŋ//bortbyting
(European folklore, also, figurative) In pre-modern European folklore: an infant of a magical creature that was secretly exchanged for a human infant. In British, Irish and Scandinavian mythology the exchanged infants were thought to be those of fairies, sprites or trolls; in other places, they were ascribed to demons, devils, or witches.