The first thing that exposed Vivian Mercer wasn’t her voice. It was the way she laughed.

For eight months, I had watched my mother-in-law supposedly forget how to hold a spoon.

I buttoned her sweaters when her fingers allegedly stopped cooperating, cut her chicken into tiny bites, rinsed shampoo from her silver hair, changed sheets after accidents she cried over, and spent endless afternoons beside her while she stared blankly at game shows as though she couldn’t understand the questions.