This article provides some interesting facts and insights. From a parent's perspective the final paragraph provides a great practical point to remember if a child does start to share a 'strange' story.
Something else to keep in mind is that children do not generally spill out the whole story—it may take several hours or even days for them to share everything. What they do is, they tell you a little bit, and then they stop. The reason is because they’re waiting to see how you react: Are they going to get in trouble for sharing this story? Do you believe them? Once they see you believe them and they won’t get in trouble they feel safe enough to share a little bit more. What people need to know is that, according to the literature on the subject, if a child discloses abuse, about 96 percent of the time some sort of abuse did occur. That’s the figure—around 96 percent.
Listen carefully to your children. Always praise them for sharing. Let them tell it in their own words. Believe them. Reassure them. They must believe they can tell you anything.