Welcome back, Christine! I believe in one of your previous questions you mentioned you'd be sailing on the seven-night Eastern Caribbean sailing on the Disney Fantasy. Boy are you in for a treat!
I'm glad you asked about the
dining attire on your cruise. That particular itinerary has one formal night, one semi-formal night and five cruise casual nights (one of which is Pirate Night). On formal and semi-formal night, kids do get dressed up as well. You'll see lots of little girls wearing their favorite princess dresses that night, so that's always a fun option. If not a princess dress, then any other fancy dress will fit in perfectly. Little boys can be seen wearing anything from a tuxedo (so cute!) to a sports coat with khakis or simply khakis and a dress shirt, sometimes with a tie.
Disney Cruise Line does ask that guests not wear shorts, flip flops or tank tops to the main dining restaurants any night, so plan to save the shorts for daytime. That being said, a very young boy dressed in dress shorts and a polo shirt would fit in just fine on cruise casual nights. Men, however, should wear long pants. If your family is like ours, there aren't all that many times back home that all four of us get dressed up in our best clothes, so it's a lot of fun to enjoy formal and semi-formal nights on the ships. Even the characters wear their best that night, and it certainly makes for some great photo opportunities with Mickey and his friends in their formal best.
I hope that helps as you begin thinking of what to pack, Christine! As always, please feel free to stop back with more questions. You have quite a bit of time until you set sail, so I'm very happy to help as you continue to plan!