Christina says she believes her son Stephin was killed by his good friend Devin. She says that after the two got into a disagreement, shots were fired and her son was left to die in a ditch by the side of the road. Devin, his former roommate and his then girlfriend were arrested in connection with the murder, and Devin ultimately pleaded guilty to negligent homicide and served two years and four months of a five-year sentence. Christina says he deserves to still be in jail. Watch her story here.

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Devin adamantly denies loading the gun or shooting the gun that killed Stephin and says he’s served his time and Christina needs to “leave me alone.”

WATCH: Woman Claims Man Who Pled Guilty To Negligent Homicide In Connection With The Death Of Her Son Is Now Harassing Her

In the video above, Dr. Phil reviews some of the evidence from the case with Christina and offers advice for moving forward.

“I see absolutely no evidence to suggest that [Devin] pulled the trigger,” Dr. Phil says. “The worst thing that you could do is decide that the wrong person pulled the trigger and therefore the person who actually did is not held accountable for you.”

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

On Friday’s episode, Devin agrees to take a polygraph test. Will the results help Christina move on? Check here to see where you can watch.

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