Kevin Williams talks about his son, Kai Williams. The 20-year-old who had just graduated high school would spend many of his afternoons playing basketball, but something changed after his girlfriend, and mother of his child, broke up with him. He became obsessed. The stalking started and over time it intensified. His ex-girlfriend, Larissa Barros, got two domestic injunctions against him. She also called authorities after the tires on her vehicle were slashed, which she says a day later was set on fire. It all ended in a murder-suicide.