Here’s a quote from John Holt about why he engaged in self-censorship during conversations with children that I find fascinating.
Many things in the world around me seem to me ugly, wasteful, foolish, cruel, destructive, and wicked. How much of this should I talk to children about? I tend to feel, not much. I prefer to let, or help, children explore as much of the world as they can, and then make up their own minds about it. If they ask me what I think about something, I will tell them. But if I have to criticize the world in their hearing, I prefer to do it in specifics, rather than give the idea that I think the world, in general, is a bad place. I don’t think it is, and for all the bad that is in it, I would much rather be in it than out of it. I am in no hurry to leave. Even if I thought the world, and the people in it, was more bad than good, I don't think I would tell children so. Time enough for them to learn all that is bad. I would not have wanted to know, when I was young, all that I now know about what is wrong with the world. I'm not sure that I could have stood to know it. Time, and experience, and many friends and pleasures, have given me many assets to balance against that knowledge, things to put in the other side of the scales. Children don't have many of these. They need time to learn about some of the good things while they are learning (as they are bound to) about the bad.
—John Holt, GWS 7, p. 11