As others have posted, you have to call if you want to include your "under 3" yo on your reservation.
Over the Memorial Weekend, we stayed at CSR in one room. I was a bit nervous moving from AKL (where we had spent the previous 8 days) to a moderate but glad to get a room on-site. (Midway through our visit, we decided to stay 2 more days. We didn't factor in the holiday weekend. EVERYTHING around was booked. We finally lucked into a cancellation.) To make a long story short, we did great. We loved CSR and will consider staying in a moderate again. We had plenty of room. We didn't even use the pack-n-play for our 2.5 yo dd. The little ones (dd and almost 5 yo ds) fell asleep in one of the full beds. I ended up sleeping with them, while our older almost 13 yo ds slept with his dad. No problem.