In the middle of a rainy Michigan night, 88-year-old Dian Wurdock walked out the front door of her son’s home in Grand Rapids, barefoot and coatless. Her destination was unknown even to herself. Wurdock was several years into a dementia diagnosis that turned out to be Alzheimer’s disease. By luck, her son woke up and found her before she stepped too far down the street. As the Alzheimer’s progressed, so did her wandering and with it, her children’s anxiety. “I was losing it,” said her daughter, Deb Weathers-Jablonski. “I needed to keep her safe, especially at night.” Weathers-Jablonski installed a monitoring system with nine motion sensors around the house—in her mother’s bedroom, the hallway, kitchen, living room, dining room, bathroom, and near three doors that led outside. They connected to an app on her phone, which sent activity alerts and provided a log of her mother’s movements. “When I went …