Pumpkin is in that stage where she is curios about most things. Also, she's into that let-me-repeat-everything-a-few-hundred-times phase. One of those things that sparked her curiosity are traffic signs. She asks what it means, what we need to do when the light changes.
Driving with her is a surprise experience. She might tell you to go faster so when can get to the red car, or whatever. Or she might say you are a slow driver, or a bad driver. And among other things she feels the need to be a police officer. If she sees a STOP sign she will start yelling: STOP! STOP DAD! YOU HAVE TO STOP!
As annoying as that can be/is I guess because of her we are becoming better drivers.