A family is a collection of people who share the same genes（基因）but cannot agree on a place to pull over for lunch. Ed and I, plus his parents and sister Doris and eight-year-old niece Alisha, are on a road trip to Yosemite. Ed wants Subway, I want. In-N-Out Burger, Doris wants Sonic. In the end, we compromise on McDonald's, where Alisha will get an action figure.

    It's a three-hour drive to Yosemite, but we're taking a little longer, as we're working in a tour of Highway 80's public restrooms. As the saying goes, “Not one bladder（膀胱）empties but another fills.” Many of these restrooms belong to gas stations. I prefer them to the high-tech ones on planes.

    We get back on the road. Ed is driving now. When all the tabloids（小报）have been read, the travel has grown tedious and anyone under age 12 asks “Are we there yet?” at ever-shortening internals. Just outside Manteca, California, we stop for coffee. At a Starbucks checkout, Ed buys a CD of Joni Mitchell's favorite musical picks. The hope is that it will have a calming effect.

    As we pull back onto the highway, it starts to pour. Then something amazing happens. As we climb the mountain, the rain turns to snow. The pines are spotted with white. We're struck dumb（说不出话）by the scene outside. For a solid 15 minutes, everyone forgets about their bladder, their blood sugar and the temperature. Alisha has never seen snow, so we pull over to make snowmen and catch snowflakes on our tongues. Then Ed realizes we need tire chains, and we have to turn back and drive 30miles to Oakhurst. “Good,” says Doris. “There was a very nice restroom there.”