....but its really only a US issue...I've seen kids looking 10-12 having vino on European flights...I think you will see the FA's use discretion if they are having many or appear drunk....here in Canada any over 18 (its 18 in some provinces 19 in others) will get served, my 17 year old nephew wasnt asked at all but the kid is over 6'. So unless its a US departure I dont think you have much to worry about.