The 92-year-old World War II veteran and his 89-year-old wife were more than a handful for the alleged attacker.
Investigators said Robert Kelly Jr. talked his way into a home in Springfield, Ohio where he had previously done odd jobs.
"I was so proud of him when he told me he was going to college. I thought that was great and let him come in and use the phone," homeowner Ruby Mathis said.
Ruby and Hugh Mathis said they thought they were helping someone who lives right in their neighborhood but it almost backfired.
"He stuck the knife out there and said 'Give me your money,' and I said 'You go to hell!'" Hugh Mathis said.
"They were talking real low, and I came in to see what it was and when I did he was standing in front of Hugh with a knife saying, 'Give me the money out of your pocket,' so when I heard that I ran to the bedroom and got the gun," Ruby Mathis added.
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