When the disciples, overearnest as ever, asked Jesus who was the greatest in the kingdom of heaven, Jesus pulled a child out of the crowd and said the greatest in the kingdom of heaven were people like this (Matthew 18:1-4). Two thousand years of homiletic sentimentalizing to the contrary notwithstanding, Jesus was not being sentimental. He was saying that the people who get into heaven are people who, like children, don't worry about it too much. They are people who, like children, live with their hands open more than with their fists clenched. They are people who, like children, are so relatively unburdened by preconceptions that if somebody says there's a pot of gold at the end of the rainbow, they are perfectly willing to go take a look for themselves.
Children aren't necessarily better than other people. Like the child in "The Emperor's New Clothes," they are just apt to be better at telling the difference between a phony and the real thing.