I guest many readers would think that Hayao Miyazaki must be able to understand a child's mind quite clearly. He says, "I am already an adult who is a lump of worldly desires." Since he is an adult indeed, he can not always understand the child feeling immediately. He loved his and neighboring children, while he watched their behavior always carefully. He made effort to understand the child ’s feeling, and he got to it as a result. If you watch them without prejudice, you can make out their behavior and feelings. That is written to his work, "Starting Point" in detail.
It is more exact to say that Hayao Miyazaki has the sensitivity to understand the children's heart. Hayao Miyazaki faces the children having humble and graceful mind and often observes them, By that activity, he can produce the excellent works.
The adult has ever been a child. Most of adults may say with confidence on the ground of the experience, “I can understand the children’s mind.” Such people would get it into their heads arbitrarily that children think like this and is doing such actions. I guess, if anything, such misapprehension would have damaged their heart. There are many things to learn from Hayao Miyazaki's way of thinking.

Why did Hayao Miyazaki make "My Neighbor Totoro"?
He says, "I want to say distinctly that I did not make the movie for nostalgia to the days. I expect that after the children saw the movie, they come to take a whim to run in a grassy place, to gather acorns, to play with going on the back side of a shrine--though it's a limited opportunity, and to fall into a flutter by peering down the space under the floor of their house. That's my hope.” (Quote from the "Starting Point").
He wanted to draw such a feeling in a flutter in his childhood, and to tell the children the feeling. That's why he made "My Neighbor Totoro." There is an impressed scene on the scene of the beginning of a movie. When May, Satsuki and their father have moved to the country house, the sisters opened all sliding screens in the house, and looked around the rooms and a boxroom. They were so excited and fell into a flutter.
In another scene, a typhoon comes, and strong wind and hard rain strike a roof overnight. May and Satsuki fear that and cannot sleep overnight. Children excite about such common affairs. It develops the children's sensitivity.
Hayao Miyazaki worry about the bad influence of that many children have shut oneself up in the room watching video or TV game all day long today. It is harmful for children to repeat the life in which they receive unwanted screen, when their five senses should grow up. And there are many stimulus images in the TV and videos. They may lose all sensation. He say that even if children watch his “My Neighbor Totoro” repeatedly, it is not good for them. The children should learn a lesson from nature and true human society. Adults must have responsibility to give children such the opportunities.