The painted wall

In the novel The Painted Wall, Otto (Ota) B. Kraus writes about his own experience in Auschwitz during WWII. Otto was one of the instructors in the children's block and his (future) wife, Dita, was the librarian for the children, of whom only a handfull survived. The book, which was originally named "The Diary", was written after the war. The story of a diary is but a literary introduction, yet the events described in the book are real.
The Painted Wall tells the true story of 500 Jewish children who lived in the Czech Family Camp in Auschwitz-Birkenau between September 1943 and June 1944. The children were kept on a Children's Block supervised by the notorious Dr. Mengele, where their instructors organized clandestine lessons, singalongs and even staged little plays and charades.
The Children's Block was intended to provide the Nazis with an alibi to refute the rumors of the Final Solution. As long as the Children's Block existed, it was a shelter and haven for the hundreds of children, who soon afterwards perished in the gas chambers.