Ahoy!
It sounds like you have a fabulous vacation planned with some time at the Walt Disney World resort and then aboard the Disney Wonder.
One of my fondest memories is swimming with dolphins in the Bahamas. They are such intelligent mammals. I recall being in absolute awe over their speed and strength.
In Nassau, there are many shore excursions offered with the opportunity to interact with dolphins. The
Dolphin Trainer for a Day is for ages 10 and up. This is the only excursion where you actually swim with dolphins.
The
Blue Lagoon Island Dolphin Observer excursion is for guests who only wish to watch the interactions.
More dolphin opportunities are the
Atlantis Dolphin Cay and AquaVenture or the less expensive
Blue Lagoon Island Dolphin Encounter. Once your cruise is paid in full, you can go ahead and reserve your shore excursions
here.
There is also a Dolphin in Depth program at WDW. It's located in Epcot at The Seas with Nemo and Friends Pavilion. However, guests must be 13 years old to participate.