We are PG with a susprise #3 as well. We booked Free Dining on the bounce back last sept and then paid off the rest of the trip with DH Christmas Bonus. Then we found out about the new baby coming. We did consider cancleing our trip but my Mom and Dad are now going to come with us and we only planning on 3 park days. So I will be there with an 8 to 10 week old in Sept.
Our DD was 4 months old for her first WDW trip, DS was 16 months old. The trip was great but we planned well for them. I recommend a Baby Bijorn for the new baby, they are the only infant carrier that was comfortable for the parents for longer than 30 mins. They are pricey but can be found in consignment stores. The Baby Care Centers are wonderful, clean and cool. I have been to all of the once but am having a problem remembering what AK's looked like. The only problem with the baby centers is that they can be hike from other sides of the park. If you or your wife (I can't remember who posted) is nursing try taking advantage of nursing on the attractions. You are ususally in the dark and have some sort of privacy. I am not one who wips the girls out to nurse in public to make a politcal point. I stay covered and find privacy while nursing. The attractions were perfect, not one person noticed and the baby was happy and fed and we could keep on with our day.
I nursed through SW, HM, SSE, TTA and GMR.
I 2nd the stroller cover, we had people offering us cash for ours in EPCOT. The ponchos draped over do not do the same thing, older kids can deal with wet, but a newborn no way.
You or your wife will also still be recovering from birth so I would take advantage of mid-day breaks you or she will need the rest too.
The Bijorn will help keep baby sitmulted and awake to avoid the up all night in the hotel room crying.
Our stroller was fully reclining and had a flip up option to make the stroller like a pram or bassinet. We would put the baby to sleep in there at night to avoid having two pack and plays in the room. I would removed the straps, by pulling them out of the back and swaddle the baby like at home and they slept great. I would also recommend NOT washing the baby blankets the day before you leave. I would wash them a couple of days before and let the baby sleep with them so they have the smell of home. As you know with older kids, smells are one of the sharpest senses in an infant.
Our Ped Oked the use of Baby Blanket brand sun screen for our kids during the newborn stage. The DR laughted when I questioned sun screen and asked me what kids in sunny climates do, get sun burned? No they use sun screen. Sun burn is very serious for baby(can cause dehydration and 2nd degree burns) so also keep light weight blankets over baby in the stoller and the Bijon/carrier. We draped our so there arms and legs were covered byt the blanket and they had a hat on their head.
Any way have a great trip and please let me know how things went with your baby!
We are looking forward to our trip in Sept. My kids are 3 and 2 now and already know the time line, new Baby in August and Disney in Sept..
Oh and this trip is really for me too, SHHH!