The independent political blog published an interview with two authors of the storybook "Lili and Braveness", which was published with the help crowdfunding. The book talks to children about child sexual abuse in the form of tales, with an aim at prevention.
The authors acknowledge that the story may be depressing for adults, but it is hard to gauge how children take it. For this reason psychologists were invovled in the work. A child who has not had any such experience does not necessarily connect the story with negative feelings. At this age the aim is NOT to give them all the facts or inform them that there are abusive adults. HOwever they SHOULD know if a situation is not ok, that they CAN say no, and that they can ask for help. We do not scare them with pedophiles on the playground but make it clear that their bodies is theirs, that they have a right to their intime parts.
At the same time there is a message to adults: believe what your kid tells you and to act on it if they do.