A 58-year-old father who fatally stabbed his 22-year-old son in the heart was enraged that his son might be allowing a 6-year-old boy who was visiting their Southeast Portland apartment to use his Wi-Fi while the boy played on an iPad, a prosecutor said Monday. Michael Lamont Lawson was paranoid that someone might hack into his computer or cell phone, and that paranoia led Lawson to plunge a kitchen knife once into his son's chest on June 29, 2015, deputy district attorney Amber Kinney said Monday.