I strongly advised DD against one book when she was 7 (Diary of Anne Frank) and as I say, we put the later books of HP on pause for DS. That was based on incidents with him getting sad or scared with some other media. At this point, DD10 can kind of read whatever, though I may tell her the content of a book if I think she won't react well (eg: Hunger Games, which she chose not to read after I described it). I just moved her into the YA section, which has me slightly concerned, but she's pretty great about talking to me about stuff.