Rooms have a max of 6 for the same price or cheaper. That means that if you are 4 you can reserve for 5 and the price will be the same or cheaper. Once you check in you will get bracelets for each reserved person. Even if you don't use the other bracelets that doesn't matter you can take them with you or have them as spares. That's what I did.
As many people that get registered on check in. So if you get a room for 4 and check in 3 adults and 1 child then these will be the people that get a wrist band that gives them access to the water park and the room.
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