Heck yes I would go! I was 21 weeks along with my second when we took our first trip to WDW. It was May so it was hot and humid and I was miserable. Now we always go in December. The weather will be comfortable for you, since the parks close early you won't push yourself, and the Christmas decorations will all be up so there will be plenty to do and see. With a young child you probably don;t go on the speedy rough rides too much anyway, and the rides your daughter likes will be fine for you to ride for the most part! Stay at one of the All Stars and take an extra day off in the middle somewhere to relax to deduct cost of your hoppers. Eat counter service and bring along snacks from home. We never have loads of money to spend, but we always have a great time. Sure, there are things I want to do that I have never done because of money, but there will hopefully be plenty of time in the future for that. I think it's worth it just to see the looks of delight of my children's faces esp since I know that when they get older they probably won't even want to go to WDW with mom and dad (although I can't bear the thought). One word of advice though: Don't sit in the very back seat of the bus, the engine gets very hot back there and can raise your body temp to an unhealthy level for the baby. Congrats!