Alice is getting a lot better on the stairs, which is a good thing.  We are still concerned about the top of our home staircase, though, because the stairs twist there and if you're not paying attention you can step down straight to the 2nd or even 3rd stair.  To keep Alice from accidentally falling there I built a little barrier out of some scrap plywood.  It's nothing fancy, but it's enough to keep her from stepping down there: