I've never made a preemie quilt or an incubator cover so didn't know what size to make this, and really didn't know what I was doing. I just needed to make it. It ended up 18" square. The little heart started out at 7" but ended up at 5 1/2" because I kept making mistakes. I decided that no child, grandchild or great-grandchild of mine was going to go without a quilt made by me.