Not sure if you all saw this on the main DIS page so I am repeating it here..
The drinking age aboard ship is 21. Valid photo I.D. is required.
Disney Cruise Line reserves the right to refuse sale and/or service to anyone.
In recognition of the expectations of our multi-national guests, for roundtrip cruises departing from European countries, where the legal drinking age is lower than 21, a parent or guardian who is sailing with his or her son(s) and/or daughter(s) and/or ward(s) who is between the ages of 18 and 20, may sign a beverage waiver allowing the 18 to 20 year old to consume alcoholic beverages while onboard. Parents or guardians may complete the beverage waiver in the Guest Ticket Booklet or inquire about the waivers upon check-in. Please note: The 18 to 20 year old must comply with all laws and
Disney Cruise Line policies related to the consumption and distribution of alcohol in Europe, including among other things, agreeing to not provide alcoholic beverages to any other person, regardless of age. This policy is subject to change without notice."
I didn't know they allowed this on the Med cruises. I plan to sign the waiver for my DS19 as I trust he can handle it no problem.