Welcome Back, Dorothy!
I often plan to do laundry while we are on a 7-Night Disney Cruise Line vacation. That way, no one runs out of clean clothes, plus there is less to wash once I'm home!
On each ship in the DCL fleet, there are laundry rooms where you can do your own loads for a minimal fee. They sell soap and fabric softener in there as well, however, I usually bring laundry soap pods and my own dryer sheets, so our clean clothes smell like home (plus, it saves a couple bucks per load!). If you are planning to do laundry, you might want to bring a couple of mesh bags to pre-sort your loads in your stateroom.
If you are bringing formal wear, and it gets wrinkly, you can always send your things out to be pressed. I have found that the
laundry services onboard is quite reasonable, and it is nice to have a freshly pressed dress to put on for formal night. It is quite magical when my dress gets delivered to my stateroom!
To locate your closest laundry room, simply ask your stateroom host/hostess. If there isn't one on your deck, you might have to head up or down just one flight of stairs to get to the closest one.
I hope this helps with planning for your large family cruise! I will keep my eyes peeled for more questions from you as your trip gets closer.
Bon Voyage and Happy Sailing, Tracy V.