A little girl in a pink cardigan, no more than four, was running up and down the hallway. Each time she passed their compartment she slowed down and craned her head sideways to look inside. She had done this three times already, and showed no sign of losing interest. He couldn’t help but laugh as she careened past a fourth time and made a screeching halt to flash them a peace sign.

On her fifth pass, he tried to speak to her. “What’s your name?” he asked in Chinese, but she just stared at him for a moment, then dashed off to continue her patrol of the hallway.