Children have no reservations. They say what they think. They trust who they find trustworthy. They do what they feel like without thinking what others think.
I wish I would be more like that sometimes. I think that is what Jesus was talking about when He said that unless we become like a child, we cannot enter the Kingdom. (Matthew 18:3)
Example:
I was playing with some children just a few days ago in a sand/gravel box. I buried my feet in sand and pebbles. One little girl said, 'I'll help you!' and dumped a whole bottle of bubbles on my feet, hoping that would un-bury them. It obviously didn't and them my feet were all sticky and sandy. I laughed and she apologized for making my feet a mess. When it was time for us to go inside, I just threw on my flip-flops thinking that I would wash my feet in a bit. The little girl stooped down and with her hands brushed the mud off my feet.
As she did that so, I was aware of the humility in that quick and simple action. She didn't stop to think that she would get her own hands dirty, but saw that my feet definately were dirty and so she wanted to clean them.