Hey Barry,
Was born and learned to dive in West Palm. It wasn’t until I moved to New York that I ever even considered buying a wetsuit. Even diving over 100’, and still never felt so much of a chill in Fl. I don’t know if you or your daughter get cold easily. I would have to agree that a 3mm would be more than enough, and even then I would just wear the top. Have a great time, have dove both of those in the early 80’s, and was plenty to see back then.