What is the author's tone in the nonfiction book, Hidden Valley Road: Inside the Mind of an American Family?

Robert Kolker writes about heavy topics including mental illness, childhood trauma, sexual abuse, murder, and suicide, with compassion and the necessary gravitas. He does not sensationalize events but presents them with the appropriate mix of neutrality and compassion. He also makes a point to address some of the psychology of childhood traumas which further his empathetic and understanding approach to the struggles of the Galvin family.