Ahoy, Sarah!
Thanks for cruising by the Disney Parks Moms Panel with your question!
I'm happy to hear you're planning to take advantage of the amazing Youth Clubs on an upcoming Disney Cruise Line vacation. We've been cruising with Disney since our girls were little, and have had wonderful experiences with all the onboard Youth Clubs, from "it's a small world" nursery! to Vibe, the teen club.
Disney Cruise Line's Youth Clubs (for ages 3-17) are awesome, and are included in the cost of your cruise! The clubs are typically open the same hours each day, and little cruisers can visit as often as they like, and stay as long as they like! You won't need to make reservations for your child to visit - they can drop in any time. Club hours are typically 9am-Midnight, but may vary on port days. Make sure to refer to your Personal Navigator (a detailed schedule you'll receive in your stateroom each day) for the hours of operation. I encourage you to visit the clubs on embarkation day, during Open House hours. You'll get an overview of what kinds of activities will be happening throughout your sailing, and you can meet the highly-trained, friendly Youth Counselors.
Littlest cruisers (ages 6mos-3yrs) can enjoy time in "it's a small world" nursery! for a minimal fee. Reservations are required, and can be made in advance when you book your onboard activities prior to your sailing.
I checked with the folks at Disney Cruise Line to see when we should expect them to release a list of Port Adventures for
King's Wharf, Bermuda. I was told the Port Adventures should be available about 5 month prior to the first sailing to Bermuda.
I hope this helps with your planning - have a magical day! - Diane W.