I have an 18-month and 3-year-old and we do day trips. What works for us is babywearing for the younger one--she'll take 2 or 3 naps on a Disney day in the carrier and will nap through rides and shows. The 3yo doesn't normally nap at home at all, but he needs a nap at Disney because it is so stimulating. And he won't use a stroller. ;( Since we don't have a Disney hotel, we always plan a show of some kind that's at least 20 minutes long around 1 or 2 p.m. He will fall asleep on dad's lap or leaning on my shoulder during the show. It's not ideal, but it seems to work for us. For example, at AK we went to the Lion King show, and at HS the Frozen show. It's not a long nap, but it seems to be enough to get him through the rest of the day without issues, and then when we pile them into the car after dinner they sleep for 12-13 hours straight. The nursing rooms in the baby care centers look nice and quiet, but my 3yo doesn't nurse anymore so that wouldn't help him. It is a hassle to go all the way back to your hotel. Hope you find something that works for your family. I was worried about naps too before we started going to the parks and I think I even posted about it once here, but once we had a few park days under our belts, we had worked out a system.