Once at work we were warned about an incident on an airplane. We were told simply to watch out for any nonsense with children and people they don't know and perhaps recommend parents accompany their children to the lavs (where it supposedly happened).

I never was able (or even tried) to confirm this incident but thought it would be fair to mention it. Planes aren't totally safe but I think with reasonable precautions, incidents can be avoided.

Even if a six year old is fine with public restrooms, plane lavs are a little different. Kids got stuck in them, panic and often can't open the door. Usually you can lift the flap and manipulate the lock from the outside. They often don't know how to flush the toilets or can't find the trash. I would help, if I were close by. As a parent, I simply organized that bathroom breaks as a family affair, all at once.