We will be traveling with my 3 year old on a 6 hour flight to the caribbean. Once we are there, we will be renting a minivan. So, we need to bring a car seat or booster with us that we can use in the van. We have a marathon and a nautilus (currently used as a regular 5 pt car seat). She is almost 40 lbs and just under 40 inches.
Should we bring the marathon and use that on the plane and then in the van? or should we not use a car seat on the plane and bring the nautilus (just the booster) or some other booster that is easier to travel with? I've also seen the "portable car seat", the tote n go...is that a decent option for the van? I'd prefer to go light with having to carry the seat/check the seat/etc...but, I want her to be safe most of all! Any opinions? Thanks!!!