There is a scene in one of the books where the narrator finds a sliver of flesh still stuck in his teeth from when he was fighting in tiger form, and that isn't a particularly gruesome scene in comparison to the rest of the books, just to be clear. Harry Potter's later installments come close but Gravity Falls and Adventure Time aren't even in the same league. I do absolutely agree with your basic point though - I also greatly enjoy all of these series watching or reading them with younger family members.