I would recommend getting a stroller for anyone ages 7 and under. especially if you're going during the hot months. The heat can really take a toll on a child and it might be good for them to sit in a stroller and rest. I have a 1, 5, and 7 year old and we'll be getting the double stroller. The 5 and 7 year old will probably take turns riding. As long as you can push it then why not. Your children will be much happier.
Depending on how tall you are I think you might find a wheel chair more comfortable!

We'll need to be at the airport by what, 4:00, 4:30? It's just the two of us, and I simply can't carry her. She says she'll be awake. Right. I'd rather have a stroller to dump if I need it. And one to dump her in when we land, too!
and walk away laughing...Who cares what people think. 