Not sure, but why do you ask? It doesn't really matter. Unlike airlines, I'm pretty sure DCL does not limit the number of carry-ons or checked luggages. So, whether a stroller counts or not makes no difference. We had 2 umbrella strollers with us when we boarded our 5/10.
You can borrow a stroller (Grayco) from DCL Guest services at no charge. We have opted to leave our stroller at home for our cruises, and simply borrow one. It's nice when we're in port so DD can ride or sleep, and DW can stash her "shopping treasures" in the basket underneath!
From what I do understand, DCL does limit the # of carryons to one purse and one carryon, so I am a little concerned about our carryons. I don't want to borrow one since we are going during a busy time and there may not be one available.
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