Back when my daughter Clio was in cancer treatment and I'd get together or chat with friends, there would inevitably come a juncture in the conversation where the friend would start complaining about one thing or another, in the way that friends do with each other—some headache at work or challenge with the kids or frustration about X or Y—and then they'd stop themselves and look stricken and say something along the lines of: "Oh my God, I'm so sorry, I shouldn't complain, given what you're going through...."