You can do a search and get confirmation, but...
As I understand it, you only get one official Photopass Plus card, and that's the one you have to have in hand for ride photos and meals (basically, the stuff not included with your regular PP card) BUT you can also get regular PP cards from the photographers that do the regular photo ops and link those to your PP+ account. So others can have regular cards to use around the parks for character meet & greets while one person holds the Plus card.
One more tidbit: if someone in your party does a PP+ ride and wants the photo, but doesn't have the PP+ card, they can make a note of the photo # and you can go back and get it added to the PP+ card later. I have heard conflicting info on how long you have to do that, though; some posts say until closing on the day it was taken and others say 24 hrs.
This is our first trip using PP+ and we are mainly in it for the ride photos. ;-) Hope you have a wonderful time!