In Japan, there is a long-run, famous anime, DORAEMON. There used to be a scene where Shizuka-chan, 10 or 11 year old heroine,
soaks herself in a deep bath tab. You could see her shoulders and head. As long as I understand, not a once in the long history.
It is well known that those scenes are cut off when exported from Japan to foreign countries. These days, you do not see Shizuka
take a bath in Japanese original episodes. Not so much different from smoking (i.e. political correctness). You will seldom see
smoking scenes in American movies. I believe only mafia members smoke in Japanese movies. In TV dramas and movies,
no fathers smoke at home. Children always wear swim suits.
In old days, no top on a five year old girl was totally okay. Still not a problem depending upon where you are. But problems happen.
Otherwise, we need no children porngraphy law. In my personal view, it's fine that five year old girl is topless if it's public beach, and as long as
you follow laws and your daughter is not annoying anyone. At hotel pools, you may want to respect their rules, even if not
in writing, just because of those changes developing in the world we live in.