It’s a delicate thing. We thought our dog was eight years old — or maybe we wanted her to be eight years old, which isn’t exactly like being a puppy, but feels like the solid if slightly overripe prime of life, when the dog and you know each other’s habits inside out, and you walk together when you want, and if you’re feeling lazy, the dog is happy to just hang out and pretend you both did some exercise and are now enjoying its pleasant aftermath. But we were lying to ourselves. She’s eleven. That’s a far cry from eight for a dog, really, and there are mornings these days when she wants to sleep in, and afternoons when she wants to sleep in, and she has started eyeing stairs with reluctance. On occasion, she’s creaky and slow to unhinge her hips when she gets up. There is nothing crueler than the fact human and animal lifespans are so out of synch. I would have been happy to have one dog for my entire life, absolutely content. Variety is very appealing in certain aspects of existence, ...