Thanks ladies I'll have to check back in as I work on it, because I have very little idea how to do this. I've never put anything like this together.
Okay so I have thin cotton muslim, will that be fine for the lining? I'll just so ahead and line everything, except maybe the puffy sleeves.
What you see is what I have. Not even a single extra scrap of this fabric. I'll measure and send DH off to buy a zipper for it today. I have one but I'm certain it's much to big. If it's meant for 6-9 months it will be easier to get a real baby into a dress if the zipper is there, this fabric has no give at all! :)