C.T.
Never had to pay to gate check stroller/car seat. Flown with airtran and delta. Also keep in mind that you can have two carry on pieces of luggage. One suitcase, 19 in. or smaller and one "personal" item: purse, laptop bag, backpack. A diaper bag does not count, is not included in the carry-ons. So that is a total of three bags you can take onto the plane, but remember that is not easy to carry with a baby. So in a way baby can have a bag too. It is a lot to carry but if you want to avoid the charges for checked luggage then load up on carry-ons.