A young princess in Arendelle married a man from another part of the country. He was a nice fellow, and they got along pretty well together. There was only one problem: every night, he'd go ice harvesting in the mountain. Sometimes he would be gone all night long, and she would complain about how lonely she was.
This couple had two young sons. As soon as the boys could walk, their father began to teach them how to harvest ice. And when they got to be old enough, he took them ice harvesting in the mountain at night. Often they would stay there all night long, and the princess would stay back in the castle all by herself.
After a while, she began to act in a strange way; at least, that is what the peasants said. She told them that her husband was turning into a reindeer, and that he was trying to turn the boys into reindeer as well.
Everybody told her there was nothing wrong with a man taking his sons ice harvesting. That was a natural thing to do, and when it came to reindeer, there just weren't any nearby. Everyone knew that.
Early one morning the young princess came running into town from the direction of the mountain. She was ice-cold. She said a big reindeer and two little reindeer had pushed her into the snow with their antlers and had tried to get her to eat a raw carrot. They were her husband and her sons, she said, and they wanted her to live with them. But she had gotten away.
The royal physician decided she had temporarily lost her mind, and he had her put in the castle infirmary for a while. After that, nobody saw her husband and boys again. They just disappeared.
But now and then the sauna shopkeeper would tell about seeing reindeer in the mountain at night. Usually it was one big reindeer and two smaller ones. But people said he was just making it up.
Everybody knows there aren't any reindeer around here ..