My son is 9 months now. We just changed him to a convertible car seat from his infant carrier/seat. He's always been amazing in the car until now. He loses his mind in this car seat. I know nothing is wrong with it and we've offered toys, snacks and I even sit in the back with him but he screams and screams and screams while in the car now. Has this happened to anyone else? Any advice on how to make him happier while in the seat?