That’s what story books are for they exist to explain that there is evil in the world & not all people can be trusted. Red Riding Hood teaches stranger danger, & other traditional stories teach other lessons. Just because these stories aren’t real doesn’t mean the lessons they hold are less valuable. Tell them a fairytale & explain how people in the real world can be a wolf but you may not see their fur or fangs. The fairytale elements allow a child to learn & they can apply the lessons when they face a situation that reminds them of the fairytale.