Ahoy, Gail (or should I say G'day?)!
On a Disney Cruise, you will see people dressed in a wide variety of clothing at dinner in the main dining rooms. The official word from Disney Cruise Line is that attire for dinners is
cruise casual. This means that your husband will be fine in his favorite shorts.
Since you are sailing on a 7-Night itinerary, please be aware that your cruise will include both optional formal and semi-formal nights, as well as a
Pirate Night. On the formal and semi-formal nights, your fellow cruisers will be dressed in everything from tuxedos and ball gowns (like my husband and myself) to khakis with polo shirts and sundresses. I have found in my cruising experience that there are fewer people NOT dressed up on these nights on a 7-Night sailing.
The bottom line is that it is YOUR vacation, so wear what you are comfortable wearing. I hope you have a MAGICal time on your cruise to the Western Caribbean!
Happy Cruising, Tracy V.