by David Sheff

About the author: David Sheff is a freelance writer.

My son began commuting between his two homes at age 4. He traveled with a Hello Kitty suitcase with a pretend lock and key until it embarrassed him, which was long before it wore out. He graduated to a canvas backpack filled with a revolving arsenal of essential stuff: books and journals, plastic vampire teeth, "Star Trek" Micro Machines, a Walkman, CDs, a teddy bear.

The commuter flights between San Francisco and Los Angeles were the only times a parent wasn't lording over him, so he was able to order Coca-Cola, verboten at home; flight attendants didn't care about cavities. But such benefits were insignificant when contrasted with his preflight nightmares about plane crashes.

One winter he was to fly not...