When I was 13, I was kicked in the solar plexus during karate class. The sensei came over to me and explained to me that I had "gotten the wind knocked out of me." And he was right. Quite literally, in fact. I couldn't breathe. Hearing that your son has a brain tumor knocks the wind out of you in a completely different way.
I gathered that fact from a fascinating story in the August Esquire by Luke Dittrich, in which Dittrich comes as close as one could, without access to Alexander's private thoughts, to showing that the book was a cynical effort to provide a new career for a neurosurgeon whose career was being consumed by malpractice suits.