We pack VERY light.
For nine of us, its 3 rolling suitcases, 1 garment bag and a carry on (including a laptop), and two umbrella strollers. Kids usually like to wear a bathing suit under their clothes when we board so they can hit the pool early.
I DO NOT pack each kid a dinner outfit for every night of the week. They each take about three dressy outfits, their pirate wear and playclothes (2 swimsuits, tshirts and flipflops). They are mostly in swimsuits and flipflops all week. I either do laundry once or send it out once (depending on how much money I have spent on Bingo) The dinner clothes are put on half an hour before dinner and taken off an hour later so they are barely worn.
My kids love the clubs and spend alot of time there and tshirts and shorts are what they wear to the clubs/lab and those take up hardly any room in the suitcases.
I am a fanatical organizer/packer. Each childs outfits are ziplock bagged and labeled with their name on it. The ziplocks are then put in the steamer trunks in the rooms so they dont have any chance of mismatching anything, and they dont rummage around messing up and wrinkling the clothes, looking for something

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