Weve been taking our now 2.5 yr old son on cruises since he was 11 months old. You will want to bring: sunscreen, hat, beach toys (bucket and shovel), favorite blankie, animal, favorite toys (if you can buy new ones for each day as they will hold interest longer-just watch out for the noisemakers at meals) lots of diapers and wipes (can be expensive and time consuming to buy more), medications (tylenol, motrin, prescriptions), first aid (small bandaids, aloe, diaper rash stuff, burn stuff (our son burned his hand and thank goodness for insurance as the dr visit was not cheap!)), sippy cups, soap/brush to wash them out, small utensils since adult size are hard to use (Babies r Us has a case that carries nice plastic/metal set), favorite snacks if a picky eater (we brought Cheerios, but I think they had them on board), car seat for the plane if getting a seat (cabs and buses dont have belts to use in ports), umbrella stroller (we only used ours in ports as it is a pain in crowded elevators and on stairs, and let our son burn off energry walking around the ship), swim diapers for the beach (not allowed in the pools unless potty trained and it is enforced), life jacket for swimming in the ocean (dont think you can take the ones off the ship), id (passport or his birth certificate), and clothes (might want a jacket for cool rooms or nights). Be sure to request a crib and high chair well before you leave home. Meals were ok in the dining room but at 2 he couldnt sit still long enough. We always do first seating. During breaks, we would take him out and walk around (he loved riding the glass elevators). The waiters are pretty good about kids. They brough crayons and paper, one entertained our son when he had the time (he missed his own son who looked just like ours), and brought his meal out with our first course, and then dessert when he was finished. We did take him to some shows (ice skating and the flashy ones held his interest or he fell asleep). We skipped excursions but might try one this next trip. Instead we walked around town, shopped, and spent a few hours at beaches. He liked the beaches the most, obviously! Dont forget to take lots of pictures as our son loves looking at his. If you have a portable dvd player, this works great during the flight/drive and in the cabin (I wanted to take it to dinner but husband wouldnt let me). Be sure to get a nap in daily (the fresh sea air, activities, and sun will help with this!) Realize that not everyone will be pleased to see your little one on board, but dont let it bother you. Just be respectful of others and take your child out if hes casuing a scene (this is where the new toys come in handy-when he starts getting fussy, especially at dinner, out comes a new toy). Have a great trip!