I am always on the lookout for unusual changeling stories and I found a very delightful one from Cornwall!
It explains how the fae of the area, the piskies, had a habit of seeking protection from humans at times. When this happened one had to help them, because kindness to them would be greatly rewarded, but to anger them would bring terrible bad luck. So when the inhabitant of a farm finds a weak little piskie baby near their home, they immediately adopt the changeling into the family as one of their own.
The changeling soon grew stronger and when they were healthy again they turned out so lively, clever and good-humoured that they became a true favourite of the family. They did have some very strange habits, but nobody paid any mind to that, because they all knew they had piskie blood.
The family was happy and prosperous and nobody ever thought of having to lose their little foundling. But one day the changeling was leaning out the open half-door, looking wistfully out over the fields, when a clear voice suddenly came calling from a distance: “Coleman Gray, Coleman Gray!”
The piskie jumped to attention, laughing and clapping their hands, and exclaimed: “Aha! My daddy is come!”
A moment later they were gone and they were never seen again.
It’s rather sad that the changeling did not say goodbye, but it is delightful to me to see a story where a child is left in a human’s care without taking another in return and the fae come back for their child in the end. So I’ll just choose to believe that the human family will have found little tokens of thanks and affection from their adopted child and their family around the farm often enough to comfort them a bit for their loss.