Welcome to planDisney Yen!
This is certainly a new question for me! Please read through the list of
prohibited items. While a pop-up tent is not specifically mentioned, I am going to guess that you will not be able to get it through security. Due to the size and nature of the item, in my experience, this will be a prohibited item. Any items deemed unsafe/unauthorized to be taken onto your Disney ship will be tagged and kept at the port. You may claim your item when you return back to the port after your cruise. If at all possible, I would have the tent or large items sent ahead to your next destination to avoid any problems or delays.
While the tent will not be allowed (or needed!) during your cruise, other items will be needed. Make sure to
pack cruise casual clothing, swimsuits, sunglasses, sunscreen, a tote bag or backpack to carry your personal items on port adventures, and a sweater or sweatshirt for cooler evenings.
Since you will be extending your vacation after your cruise, you may need to do some
laundry. You will find each ship has laundry rooms if you want to toss in a few loads. I like to do a load or two and not have to pack quite as much, especially if my whole family is traveling.
With your cruise just around the corner, please read
Know Before You Go and complete all pre-cruise documents. This will make the boarding process smooth sailing and get you onboard your beautiful Disney Cruise ship!
Enjoy your first Disney Cruise and we will SEA you onboard real soon!
Cathy