Comment about a story book borrowed from library

Last night I read a book titled "When Bad Things Happen to Good people". This book was so interesting. After finishing the book, I felt the writer's view was correct. Now I am going to give a brief summary of that book.

Aron was an innocent boy. He was only three years old. His parents were good persons. They tried to do what was right in the eyes of God. They really believed in god and the goodness of the world. One day their son got very sick with a disease called 'Progeria'. How could it be happening to them and to their son if what they believed about the world was true? There is only one question which really matters 'Why do bad things happen to good people?' They happen because god is a righteous judge who gives them exactly what they deserve. That's karma.