M.A.
My DD is 4 and I have been painting her toes and fingers for a year. I just get "Insta-Dry" so that it dry's fast and doesnt get on the carpet. As far as "safe"? If they arent eating it, it should be OK. Would'nt you think that if it is OK for you, it should be Ok for them?
It has been one of many things that we do to spend good ole' quality time together.
Its nail polish.