I'm thinking this only makes sense but you never know. I assumed that since we have 5 people, they would have to put us in a room with enough beds! We have a Savannah view but the ressie doesn't specifically say anything about bed arrangements.
Did you book a deluxe room? Those rooms have a daybed, but regular rooms only accomodate 4, plus a child under 3 y/o. I wouldn't assume that you'll get a bunk bed unless you request it, and it's only a request.
My youngest is 5. I don't see where it says "deluxe" on my ressie. It is through DVC, so I guess I better call Member Services and make sure they booked the right room!