Who's in trouble?

So today in school, the teacher had to get onto my classmates for being to loud (at least I think that is what is was for). Of course, I wasn't being too loud because well, I can't talk. But as she was instructing them to quiet down, I decided that it was pretty funny and started laughing. I probably should of gotten into trouble for laughing but I didn't. Who can discipline me when I have a smile like this.
I tend to do this at home too. Mom and dad may try to discipline me, especially when I chew on my shirts. They will try and tell me to stop chewing on my shirt and then again in a stern voice. I laugh every time. Anytime someone tries to be serious, it cracks me up. I just can't help it.