Before he developed Alzheimer’s, my grandfather was stern and taciturn, but after the plaque started to build up around his synapses, he turned into a different man, and in many ways a better one. He started to laugh at things, like the way one of our pigs would chew bubble gum, or how the barn kittens played in the hay. Normally these sights would have caused him to grumble or even throw a rock at the animals for not acting the way he felt they should. A few times, when my brothers and I were fooling around and not doing our chores, he’d pitched shards of limestone at us. My grandfather frightened me, and I tried to avoid him, going out of my way to make sure we didn’t spend time together. But the disease changed him.