Second World War
You may feel that you don't really want to read about the Second World War, in case it's too upsetting for you. But it did happen, and it happened to children as well as adults. All these books are set in real situations, though they aren't necessarily true. I promise you, there is nothing in the recommendations for younger readers to give you nightmares. You may have to be a bit tougher to read some of the recommendations for older readers.