Get
trip insurance. Hopefully you won't need it, but if something should happen you will want it. My daughter enjoyed the Oceaneer's Club at your daughter's age. They usually do a Pluto's pj party in the club on 1 or 2 nights. They give the kids a pillowcase to color, watch cartoons, dance, etc. All activities will be listed on the app. If you think any of you might get seasick, start taking Bonine(otc med) the day before your cruise starts and continue every day even if you feel fine. Waiting to take it when you are already ill, is too late. I also take ginger candy with me and it helps. Don't be surprise if after the cruise you have a slight swaying feeling. Can sometimes happen for a few days, I've only had it happen 2 out of 8 cruises. If you book excursions through Disney they handle transportation. If you go off on your own, make sure you head back to the ship at least an hour before the ship leaves. And make sure you know when to be back! The ship won't wait if you are late. Search pier runners on
Youtube and you'll see. Some things my family has enjoyed on the Fantasy are things that you just show up and do, so no planning required--mini golf, midship detective agency game, shuffle board, trivia, and the nightly shows(get to the theater 30mins before if you are picky about your seats, otherwise 15 mins) Jack Jack Diaper Dash when they race babies in the atrium is hilarious. Not sure if they're doing this again, had stopped after covid. You'll get a lot of helpful info from this board. You have to be careful about some stuff on Youtube. Some people will post things like taking items to guest services for character signatures.
DCL stopped allowing this 10 yrs ago, yet some vbloggers still say you can do it. Makes me think they've never cruised. You can take autograph books to the character meets.