Because the hen needs a lot of physical strength to lay an egg, she doesn't leave the nest until she lays a good egg and has a rest for a certain period of time. At this time, its spirit is in a state of excitement, so it has been giggling.

Another function of hen's cry is to attract the opposite sex. If you have been to a chicken farm, you can often find a rooster waiting beside the chicken nest. When hens leave their nests, they will go up to mate. Eggs born the next day are the easiest to fertilize, which means chicks are easy to hatch.