Norbert Kilian was born in Nürnberg in 1957. Since he was three years old he always had a dog at his side, he has been involved in sled dog sports for several years and has been an animal protection activist since the age of thirty. At the age of 49, Norbert Kilian was diagnosed with cancer, but refused any conventional medical treatment and successfully carried out self-treatment. In recent years, Norbert Kilian has published three books on cancer healing, one of them on cancer treatment in dogs. In this book he writes that he believes in rebirth and transmigration of souls in all living beings. Based on this statement, he received several letters from readers who described their experiences with reborn pets. Norbert Kilian pursued this topic with joy and common sense and found stories and reports of experiences on the internet, in magazines, books and newspapers. From this long lasting search the book "They come back" was created.