I’m wondering whether what happened to Carla could happen to me. I always imagine the worst-case scenario. Right now, for instance, I’m calculating how long it would take me to jump out of the car and reach Nina if she suddenly ran and leapt into the pool. I call it the “rescue distance”: that’s what I’ve named the variable distance separating me from my daughter, and I spend half the day calculating it, though I always risk more than I should.