little thing

Hi! I'm Dug.
Today, I saw the little girl when I went to college on the way.
She was riding on the bicycle and I was driving my car. 
I thought she would go across the road. I stopped my car. But she stopped, too. And she started swinging her right arm.
"What she is doing?" I thought. 
Soon I understand. It means you go first. 
This thing made me feel so happy.
Then, I raised my left hand (it means thank you for waiting), and I passed in front of her. 
Recently there were a lot of sad things about children. But I could see little good thing about children.