During further meetings with Don Alberto, Martelli learns that Don Alberto's mother has a young child, a six-year-old deaf and mute girl with an intellectual disability. Martelli becomes convinced that the little girl is a witness to the killings after seeing that she compulsively pulls the heads off her dolls as if imitating the strangulations. One doll's head, that of Donald Duck, is found near the latest crime scene.
During further conversations with Don Alberto, Martelli learns about his mother's six-year-old child, a deaf and mute girl with an intellectual disability. Martelli becomes certain that this child may be a witness to the murders after noticing her behavior, which bears resemblance to the strangulations he has seen at the crime scenes.