A few weeks ago, we took our (then) 9-month-old baby on her first cross-country trip, complete with a layover. We lost 3 hours heading from west to east and forced her to suffer two separate ear-popping take-offs. To boot, we'd subjected her to an hour-long car ride, remote parking at LAX, a shuttle and airport security before the aerial adventure even commenced. It was a long day for us all, but baby girl was in a great mood anyhow. She smiled, clapped, cooed and made many friends. She was actually impressively well behaved. The day was of course not without incident. During the first flight's departure, my husband was holding the baby. He had her wrapped in a soft, warm blanket and was trying to feed her a bottle to ease the discomfort of ear popping. She didn't seem interested in the bottle, even though she'd not eaten much that morning. So he propped her up, she let out a giggle and then he smelled it. He nudged me. He cautiously moved a corner of the blank...