1941 Baby Dress and a new blouse problem

Thanks to Vintage at Goodwood I finally had a reason to put the baby in my pride and joy, Simplicity 1941, seen here with a cardigan I knitted from a 1950's pattern. So I actually now have a photo of the thing being worn. And it now has stains on.

At Vintage at Goodwood I fell in love, with this pattern. But how (can) I scale it down? It was only £2 I couldn't resist. Look at the excellent way that you can make a sheer blouse to wear over the other, making it a great day-to-night possibility. Sigh.