His only son,
Theo Dahl, suffered a brain injury when his baby carriage was struck by a taxi when the boy was just four months old. The most
serious of his injuries was hydrocephalus (commonly known as water on
the brain). Dahl got together with a pair of friends--a neurosurgeon
and an engineer--and created a device called the Wade-Dahl-Till valve
to alleviate cranial pressure. Theo recovered before the device was
perfected, but it allowed thousands of others suffering from
hydrocephalus to recover from their injuries. His book "Charlie and the Chocolate Factory" is dedicated to Theo, who
almost died.
