I am 37.5 weeks with baby #5. I have a 6,5,3, and 1 year old. We have a toyota Sienna. We are desperately trying to get a safe combination of car seats accross the back of the van so that my two older children can buckle in safely and conveniently on their own. I realize that we could get a larger vehicle (however I don't want to pay for gas or pay for the vehicle itself, if we had to do this, we would consider and SUV). Any thoughts? Thanks so much for your time.