Couple Who Befriended Suspected ‘Killer Grandma’ Lois Riess Lived in Fear

One husband and wife were living in fear during the four weeks accused killer Lois Riess was on the run. Tess Koster thinks she could have been the next victim. “It might have been me,” she told Inside Edition. The Kosters were good friends with Riess and her husband, Dave, in Minnesota. They were vacationing in Florida, where they own several rental homes, when they heard Lois was suspected of shooting her husband to death and taking off with $11,000 to finance her gambling addiction.