Was that out loud?

My daughter is 7. She thinks she is 17, complete with the attitude. Not a good idea. Paul is out of town so it's 2 against one. She thinks. I will not out-numbered or out-maneuvered. I am not a benevolent dictator. I am a dictator plain and simple. Do what I say. No questions. No arguments. No debates. No discussions. No negotiations. I took the kids to their art classes. I let Sara play on the computer. I took them to a friend's house to decorate Halloween cookies. We had to stop at the store briefly. Sara made the fatal mistake of saying (complete with snotty tone) "if I can't ride in the cart, then I will not cooperate". WHAT??? Did my 7 year old really just say that to me? I looked at her in the rear view mirror with a combination of shock, horror, rage and disgust. Then I pulled over so I could handle this incident safely. Her attitude quickly changed when she realized what she had said. Punishment has been rendered. She has lost cherished privileges. In addition, she is not allowed to speak to me until I decide she can do so politely. It's sort of a reverse silent treatment. Guess what? It freaks her out. Brilliant on my part. Not to mention a few peaceful minutes in the car. I may be on to something. It may be very quiet in my house when she is a teenager. We may have to brush up on our sign language skills.