Thank you for all of your really good advice. I plan to write a detailed trip report at the end of our cruise to give my own experience with cruising with a baby. I also want to give my review of our unusual Stateroom 1054–4 of the 8 of us (including the baby) will be on that space.
So far, what I have gleaned from your posts:
1. Have realistic expectations. The Serenade of the Seas, and cruise vacations in general, were not designed for babies. Baby will cry more than once, and you need to roll with that and always be considerate of other cruise guests. Get up and walk away from the table if you need to—you brought the baby, and your fellow guests did not.
2. Have plans and backup plans for child care. The 7 adults—mom, dad, aunt, grandmother, great aunt (me), and other relatives—need to have a schedule for baby-watching “turns.” Use ship-provided child care when it makes sense and if the baby likes it. (Her mom and dad need time to relax, too. In our case, the mom and dad originally booked this cruise to go by themselves—the rest of us (okay, me) piled the rest of the group onto the roster.)
3. Pack all the stuff!!! Extra diapers, wipes, toys, so many clothes, hats, beach toys. Bring all the snacks!!! Bring the baby-version iPad!!! Baby needs those things from home to feel at home.
4. Most importantly, ENJOY the baby. Play. Take pictures. This is family time in a different setting.