I could feel everybody watching us, wondering what was wrong with us, and whether it would kill us, and how heroic my mum must be, and everything else. That was the worst part about having cancer, sometimes: The physical evidence of disease separates you from other people. We were irreconcilably other, and never was it more obvious than when the three of us walked through the empty plane, the stewardess nodding sympathetically and gesturing us toward our row in the distant back.