(This is your 4 year old autistic son named Taro!! If he is sad, scared, or anxious, which he is often, he will yank on his sisters hair, very, VERY hard. Her name is Katie. She hates it, but he won't stop. He needs the stimulation!! If he doesn't, he will scream, break things, hurt people, puke, and chase his sister until he gets it.)

Taro: yanks his sisters hair as hard as he can while crying sister hair nice...

Katie: screams loudly in pain