Jeff Bezos' fiancée, Lauren Sánchez, published a new children's book on September 10. Karwai Tang/Getty ImagesLauren Sánchez, Jeff Bezos' fiancée, has published a new children's book.Her former yoga instructor now says Sánchez stole the idea from her.In a lawsuit, Alanna Zabel said Sánchez sought to intentionally "inflict emotional distress."Jeff Bezos shared a rave review for "The Fly Who Flew to Space," the new children's book by his fianceé, Lauren Sánchez.Bezos titled his review "Six Stars" on Amazon, where the book has garnered a 4.8 out of 5 stars since its release earlier this month.