Yes, include the non-eating child in your reservation. They need a headcount for the reservation. Any reservation that you make on-line will only allow you to select # of guests and then on your confirmation it will say # of adults, but it doesn't matter if they are adults or children. For example, when we make reservation for our family of 2 adults and 2 kids, it says 4 adults. Then, when we check in we just tell the hostess 2 adults and 2 children. They always asked us the ages of the children, so in your case you would say 1 for the baby, and then if it's a character meal or WOC or Fantasmic meal, you wouldn't have to pay. When we went to Ariel's Grotto when DS was under 3, we weren't charged for him and he was given a portion of Mac n cheese for free (and it was a very generous helping.)