On April 13, 2011, Christina’s 20-year-old son was shot and left to die in a ditch by the side of the road. Christina says she’s convinced his good friend Devin pulled the trigger and killed her son after the two got into a disagreement.

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Devin says he did not load the gun or shoot the gun that killed Stephin, he was just there when it happened. He pleaded guilty to negligent homicide and served two years and four months of a five-year sentence. He says Christina needs to accept that he’s done his time and leave him alone.

WATCH: Woman Confronts Man She Says She Believes Killed Her Son

Claiming she’s convinced the wrong man was given a life sentence for her son’s death, Christina suggests Devin take a polygraph exam, and he agrees. Watch the video above for the results – and Christina’s response.

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