We are planning a trip to Omaha Zoo next month, with a 3-1/2 year old and a 17 month old. Tips/tricks/things to bring?
.
.

We only have a single stroller, so I'm debating on renting a double or borrowing one.. but the 17 month old typically HATES riding in it. I have a K'tan that I haven't used since she was a baby and I imagine would be hot. Good one-time-use carrier I should look for used as an option?

Bring a cooler? Snacks? Backpack vs diaper bag? How do I handle nap time for dd?
This is our FIRST vacation so help a girl out!