The first sign of trouble arrived by text. On Dec. 17 at 2:33 p.m., my younger sister, Melissa, pinged me from Houston to say that our 78-year-old father had veered off course while driving himself to a medical appointment.
“He has missed his exit,” she wrote. “I don’t want to call him and tell him because he will be pissed that I am tracking him. What do we do?”