>> reporter: megan's younger sister caitlin didn't know the name either but realized this woman mary was someone he had taken to dinner in 2010 during an off period with kimberly. >> i remember him saying he was going out to dinner but, yeah, nothing ever came from it. >> reporter: but now this mary was on the phone. >> she was very, very upset. [ crying ] >> stay with me. this is gonna be okay. relax. i kept her on the phone purposely, as long as i could, and while we were talking, i had my staff scrambling to get somebody in law enforcement to her home. >> reporter: almost 400 miles south, officers in virginia brought mary to an interview room. she was the second woman in three days investigators were speaking to about the murder of the superintendent. >> i'm glad they have these here. i just might need them. >> oh, okay. >> reporter: mary says she and keith first developed a relationship on match.com. she'd separated from her husband and had moved with her four children to upstate new york. after 11 years of marriage, she says she was trying to figure out how to get back into the dating game.