We need to help people to accept some tragedy as truly random. Jesus' life is the clearest evidence that a person's suffering is not proof of that person's sin. To deny this reality leads to cheap grace which saves nobody. Drunk drivers kill innocent people. Racist people injure their neighbors.
Violent people injure their loved ones.
Not every tragedy is the result of sin, but some sins do cause tragedy. Perhaps the best way to visualize this is a small circle inside a large circle. The large circle encloses all tragedies. The small circle encloses only those that are caused by our sin. We cannot do anything about the tragedies that lie outside the small circle, but Christ calls us to repent so that we might avoid the tragedies of the small circle.