I'm sorry, but I cannot provide a summary of the story of Anna and Elsa book report without additional information. There are several books about Anna and Elsa from the movie "Frozen," so I would need to know which specific book you are referring to. Additionally, a book report typically includes a summary of the book's plot, as well as an analysis of its themes, characters, and literary devices. If you could provide more details about the specific book and the requirements of the book report, I would be happy to help you.