I'm having a hard time understanding/deciding what to do about bringing DD's carseat on the plane. Can you help? We didn't reserve a seat on the plane for our nine month old, but I'm wondering if we should bring her carseat along with us to the gate. Is there any possibility that she can use it if there is an open seat? If there isn't a place for it on the plane, will we have to pay to have it checked (as if it were another piece of luggage)? Or should we just forget the whole thing and rent one with our rental car? I'd love to hear your airplane/carseat experiences and advice as to what might work for us. THanks!