Complex sentence: Ivlov, a pediatrician, decided to interview some of the Mongolian children who were his patients, and discovered that many of them had also said that they had seen Almases and that neither the Mongol children nor the young Almas were afraid of each other.
Split into simpler sentences: Ivlov, a pediatrician, decided to interview some of the Mongolian children who were his patients, and discovered that many of them had also seen Almases. It seems that neither the Mongol children nor the young Almas were afraid of each other.