J.G.
LOL Sorry I hate to laugh and I know it's not funny but it is a little funny. How do you know this girl and her grandmother. If they are friends, I would just say something straight out and maybe suggest getting the kid some wetwipes to use. Another thing is, the water is pretty clean and if it's not irritating her little butt it's probably fine. Public toilets are dirty, yes but is everything else. Did you know that ice machines in restraunts have more bacteria in them then toilets do? Unless it is really posing a problem I wouldn't not worry about it. Hope this helps a little.