I am blessed to have the bedroom I had as a child as my sewing room. I would be embarrassed to take a picture of it right now, though. We recently remodeled the kitchen, dining and living room and it is packed with "stuff" that doesn't really belong in there. I have carved out a niche that includes my ironing board and sewing machine so I can work on small projects, but it is time to get things moved around and put where they belong so I can really get to work now that the weather is starting to change. I have two floor to ceiling gorilla shelves that line one wall and give me lots of storage space for fabric and supplies. And my husband recently bought me a ginormous cutting mat that exactly fits on the 3-foot by 5-foot craft table I bought last summer at Joann.

I never had kids, so take this with a grain of salt.
I would not have a sewing area double as a nursery. Between needles and pins and hot irons that could be pulled off the ironing board by the cords I'd find a room with a door that I could close behind me. But that's me. Obviously, you've already safely shepherded a child into adulthood and kept him or her safe enough, long enough to have babies of his/her own!

If you google "closet as sewing area" you'll see many, many, MANY clever ideas, from Martha Stewart to wikihow. There are some clever adaptations of armoires into sewing stations.