We are hoping to take our twin (then 26 months) grandsons to WDW next year and we always get a rental car. I remember reading here (some time ago) about a system that attaches the carseat to your luggage for wheeling through the airport, which would be fantastic. That way, we could take their carseats to use on the plane, then in the rental car. We will rent a double stroller (offsite) to use during the whole stay. Anyone remember what these systems are called? or have a link? thanks so much, this is very exciting for this gramma.