What is the saddest book in the world?

There may not be a saddest book, it just depends on people's opinion. My opinion is Mockingjay. WARNING HUGE SPOILERS! There are many painfully emotional flashbacks of her dead father, Katniss visits her home after the government bombs it with futuristic military hovercrafts, and she finds her Fathers coat that he used to wear, and visited Peeta's demolished bakery. Primrose dies, President Snow kills her. Guaranteed to make you cry. Check out my other answered question, What is the plan for the Illuminati in the future.