The fluorescent lights in the produce aisle of the local supermarket always seemed to hum at a frequency designed to give me a migraine. It was a Tuesday, two days before Thanksgiving, and I was holding a butternut squash, trying to decide if I should bother making the soup my son, Greg, claimed to love so much. My phone buzzed against the cool skin of the vegetable. I looked down, expecting a list of last-minute items.