Christina says she'll never forget the night six years ago when she discovered her son Stephin's dying body.

“I found my son Stephin lying in a ditch and as I was running up to him, all I could see was the side of his face was blown apart,” says Christina.

Christina says she believes the 20-year-old’s good friend Devin was responsible for shooting her son and leaving him to die, after the two got in an altercation.

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“Devin was really mad and wanted to fight Stephin. Devin was saying crazy stuff to my son on speakerphone, saying he was going to shoot up our house,” Christina claims. “I firmly believe that Devin murdered my son.”

In the video above, Christina describes the events that she says occurred the night her son was killed, including finding his lifeless body and attempting to hold his face together so she could perform CPR.

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

Devin, who adamantly denies pulling the trigger, was initially charged with and tried on second degree murder and second degree attempted murder. After a mistrial on the original charges, and facing a new trial, Devin pleaded guilty to negligent homicide. He received a five-year jail sentence and was released after serving two years and four months. Devin’s former roommate, David, was convicted of second degree murder in connection with Stephin’s death and is serving a life sentence.

WATCH: Man Pled Guilty To Negligent Homicide Of Friend But Says He Didn’t Pull The Trigger

But Christina says she is convinced that Devin killed her son and should still be behind bars.

On Friday’s episode of Dr. Phil, Christina comes face to face with Devin for the first time in over a year and demands the truth from him. Will she get the answers she's looking for? Check here to see where you can watch.

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