The grisly murder scene unfolded behind a front door where four bullet holes tell only part of the story.
"There are so many theories about why it happened or what happened, but there’s no solid answers," said Barbara Strain's grandson Bryan Strain.
It was Wednesday morning on March 6, 2013. Bryan Strain woke up to loud popping noises at his grandmother’s home on Highland Drive in Duncanville.
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Seconds earlier, Barbara Strain answered the door but didn’t recognize the man standing on the other side.
"She shut the door in his face and started to walk towards the living room, and he shot four times through the door," Strain said.
Every single bullet hit the 74-year-old great-grandmother in the back.
"I watched her die. I watched her last moments, and it was pain and fear and that’s the last thing she ever knew," he said.
In the very beginning, Duncanville detectives did have some leads. They were able to retrieve a partial fingerprint from ballistic evidence, and they were also able to rely heavily on the eyes of an 8-year-old boy.
Bryan's young son witnessed the murder.
"When she hit the ground, she fell right next to him," he said.
It was a horrific set of circumstances, but Bryan’s little boy remembered the man at the door and came up with a description.
Despite the news coverage, the case soon went cold.
"People know; they just won’t come forward," Strain said. "They’re afraid, or they don’t want to be looked at as a snitch."
Strain believes the murder was drug related and that his grandmother inadvertently got caught in the middle.
"If it was drugs or someone I introduced into the family, I should have told them to get away and stay away long before this happened, but I didn’t do it," Strain said. "I have a lot of guilt about that."
Guilt, grief and obligation to his grandmother motivate Strain to seek justice. Duncanville Police said the case remains open and active.
Anyone with information is asked to come forward. There is a significant cash reward being offered if the case if solved.