As I queued up to board my flight, someone tapped my shoulder. I turned and received a warm greeting. “Elisa! Do you remember me? It’s Joan!” My mind flipped through various “Joans” I’d known, but I couldn’t place her. Was she a previous neighbor? A past coworker? Oh dear . . . I didn’t know. Sensing my struggle, Joan responded, “Elisa, we knew each other in high school.”