GRAND ISLAND, Neb. The boy -- 9 years old, neatly dressed, a very polite child -- walked up and extended his hand. The gesture caught me by surprise. I was in a Wal-Mart store here -- and this was not an encounter I had come to the store expecting. "Thank you," the boy said softly. He smiled. The adults with him -- they are his foster parents -- then introduced me to the boy, and to his two younger sisters. "He's been wanting to say thanks," the foster father said. I had to turn my head away, because I didn't...