Yes, this is an old saying, because in the past, every family had more than two children, and parents didn't have much time for their children to live. They all grow up naturally, as long as they don't go out of line. But every child's personality is different, and some children need the attention of adults, so they will be out of line. For example, when boys fight, girls will spoil and cry to attract their parents' attention.

Therefore, parents will pay more attention to these out-of-line children. In order to make them quiet, they will coax them and give them some delicious food. At that time, candy was the best snack to coax children, and it would give more fun when distributed, so there was a saying that crying children had candy to eat.

Now this kind of words is used in social interpersonal communication and is also very useful in work. For example, people who can speak appropriately and show weakness in interpersonal communication will be noticed. I will be more helpful when something happens.