hmmmm, that is a really great question. Technically the dress code states no shorts in the dining room during dinner hours. I really don't see a problem with nice shorts, a nice shirt and nice sandals or casual shoes for kids that young. What i would do to be on the safe side is to pack a pair or two of cargo or dockers type pants for your little guys, once aboard i would seek out the Maitre D and ask him if it would be proper for your guys to wear dress shorts/with a nice shirt on casual nights. We have done this in the past if we weren't sure of an outfit, the Maitre D is very appreciative of things like that. He will most likely tell you that the shorts will be just fine.