At that age mine wouldn't get in a stroller if you offered him cookies. If your child doesn't usually use a stroller they might protest. When mine was younger, three or so if he was too tired and for whatever reason we didn't go back to the room, I rented one. There was no question of me carrying him, he was too heavy. I don't think he ever fell asleep in it but did usually fall asleep on transportation. I just woke him, since I was a single mom he was pretty good about it. I think planning on breaks, go back to the resort or even just rest in the park should be OK. Then play it by ear if you need to rent one do, don't hesitate.