I think that you will be lucky to get any meaningful discounts as that is peak time. Several of the cruise lines, notably RCI, have family cabins but more than that I don't know....regards ....Nei.
Have you looked at MSC Cruise line - their policy is that children sharing the same cabin as two adults travel 'free' on the cruise. The only thing they have to pay for is the flight plus Port Taxes.
Christmas and discounts are not two words that go together when cruising. You need a minimum of 5 pax to get the Family Stateroom [sorry Neil!] but with 4 in a room you should get a good 3/4 pax discount.
That's ok... I wasn't stating fact purely speculating and I know you knowledge of RCI is brilliant ....so cheers...regards Nei.
Fred Olsen is a cruiseline that does give decent discounts for families on selected cruises (family friendly) they discount for a 3rd and 4th person sharing a cabin (although there is a limit on the cabins which are fitted with extra (pullman) berths)for kids aged 2-12 they will pay only 15% of the adult fare for uk departures (it will be a bit more for fly cruises though to cover the flights)and good news is there are two of Freds ships in the caribean next Xmas and those cruises are family freindly!