I don't know what. I just came from parents house and my little nephew was there and I had him laughing so hard, he didn't want me to stop. I'd pretend the ball was too hot to hold and I'd yell. He couldn't get enough of it. I could have done that all day and I don't think he would have tired of it. I had to quit because I was working up a good sweat. They are so cute when they're little.