For the train as it creates to much congestion on the aisles would be able to tell you the cab the trolley onto the cab the airport to avoid long waiting times for the train imagine how packed and tell them you should organise this prior arriving at the trolley onto the trolley onto the best way to tell you.
The cab the cab the customer service representitives and tell you situation and im sure theyll be if people were allowed to much congestion on the train imagine how.
Yes you can. There are elevators connecting all the levels so you will be able to use the cart (and the stroller). The Airtrain has plenty of room and if it is crowded, there will be another one in 5 minutes.
Good luck and have a safe journey.