After that, the ogress and her brood cleaned up their images. Grýla decided to send her sons into town only 13 days before Christmas, and they were instructed to spread holiday joy rather than fear.

By 1746, Icelandic youngsters were so terrified of being eaten, they wouldn’t leave their homes. So the government stepped in and put a ban on using Grýla as an intimidation tactic.

The family’s black cat, named Christmas Cat, only ate once per year. He waited until he could watch children unwrap their gifts at Christmas, then he would eat anyone who didn’t receive a piece of clothing.

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One at a time, wearing a red-and-white suit, the boys now travel down from the mountains and place gifts in shoes that children leave on their windowsills. If the child of the house is good, they receive a small toy; if they’re bad, they get a rotten potato. But the bad kids figure rotten potatoes are better than being eaten, so they aren’t too put off.

Each of the Yule lads has his own method of causing madness in addition to the rotten potatoes–corresponding with the names you see in the drawings above. Although many of these methods are rather tame, there is nonetheless something disgusting to each. It's hard to picture anyone being happy about having each of their bowls licked by a mischievous lad.

In recent years, many Icelanders have attempted to return the Yule lads to their pre-Santa roots, with modern depictions showing them back in their Middle-Aged garb–brown and black rags. During the holidays, you may see people dressed up as Grýla's adult sons in their woolen suits.

What happened to the Christmas Cat? He’s still prowling around during the holidays. In fact, he’s probably the reason why children still beg their parents to put socks under the tree every year.