Wanting to ask advice about something sensitive from a large group is one.

There is so much wrong with this statement. Internet "experts" are one of the scourges of modern life, whether it's self-proclaimed medics, those pushing cockeyed diets or pseudo-scientists and the like. Advice of this sort should be sought from properly qualified people where confidentiality is assure

Just by coincidence I made such an anonymous post a few hours ago. It was not on one of the 'social giants' web sites but still a moderately well known one. The issue concerned how I had missed a case of paedophilia for years in a neighbour's child because the possibility did not occur to me. I made the post anonymously because all the people involved are still alive, but I did want to give the message that a child visiting your house extremely often might have other reasons beyond just how much they like your children.

I regard Mudcat as sufficient small scale that posting this will not risk the privacy of the people involved .