It really doesn't matter. Cancer runs in Barb Kunkel's family. Her mother died of mouth cancer. Over the years, scientists have uncovered genetic mutations that cause several types of cancer. In adults, the genetic code can be crippled by factors such as the environment, diet and use of tobacco.
Childhood cancer is different.
Scientists believe genetic mutations occur spontaneously in children's cells. These mutations are unique to the cancerous cells and cannot be inherited. Jakacki made it clear to the Kunkels that Hannah's brain tumor has nothing to do with genes or a family history of cancer. It's like lightning that strikes. Gerber, who as a chaplain helps parents understand a terminal illness, tells them it's not necessary to have an explanation.