Write a story or legend about the folk customs of the Spring Festival (50~ 100 words).

Legend has it that in the early days, there was a little monster who liked to touch the head of a sleeping child from house to house every New Year's Eve, but as long as the child was touched by this little monster, it would be crazy and silly in a few days, so adults had to stay up late to see the child on New Year's Eve. But that night, an old man watched a child, but in the middle of the night, he couldn't stand it any more and fell asleep. Just about to touch the child's head, suddenly a golden light flashed under the pillow and the little monster was driven away. Afterwards, it was found that there were several copper coins under the pillow, so people formed the habit of giving their children lucky money.