If your child were traded for one of the faery people’s or unseen people’s children, the replaced child would be a changeling. This could happen if you did not take certain precautions after the baby was born and before it was baptized. If it was baptized, it was safe. You could for example put a knife the boy’s bed and a pair of scissors in the girl’s. You could add a hymnbook with them and/or you should make sure to add some ash in the water, which the unbaptized child was washed with.
If your child was replaced, it was easy to recognize. It would lie and scream with a horrible sound, it will eat a lot without growing. It was just the head that would grow. “A big head and little wit” as it says in some folk legends. It would not be able to talk or walk, at least not when others were there. It would be deformed and ugly, just sit, and rock in a chair.
When the “replacement” occurred, there were certain things you could do. The first one could try to reveal the swap the replaced child would leave by itself. You could leave it alone and see what it did, or you could try to do incredible things to make the changeling talk.
Otherwise, one could bother the changeling until the unseen people came and took the child and preferably made change back. The harassment could be that one went out into the woods and beat the child three Thursday evenings in a row. Lay it on the floor and sweep garbage over it or pinch them in the nose.
There are folk legends about the changelings who lived on the same farm for several generations.
Of course, behind these folk legends, there are a much crueler story, a story about having a child that is different from other children, and because this was a shame, it was easier to say that your child was a changeling.
On a farm in a place, called Nes there was a strange old man who they believed was a changeling. He had been living on the farm as long as the people there could remember. He could not speak; he just spoke with eerie grunt. Besides, he did not use regular pants, but a kind of a white skirt. To the people he had always been old. Evil he was and he ate almost all the food on the farm.
The people on the farm was incredible tired of him. During the Christmas season, they had had enough. They decided that they were going to cook a tiny little porridge in a large pot. In the porridge, they put so many spoons as they could. Then put the pot on the floor and walked out of the room. They stood around the house and listened. The old one was now alone in the room; he walked over to the pot and stared down on it. Then he began to laugh and talk: “I’m not that old, but not young I am either. I have seen the woods here three times cut and grow, but never have I seen so little porridge in a large pot.”
This was evidence that the old man was a changeling, but if they got rid of him, the folk legend does not tell anything about.