Fifteen-year-old Reesa was brutally murdered in her grandparents’ home on June 15, 1984. Her sister, Jodie, who was 13 at the time, says she was a main suspect – which became the town gossip -- but the case turned cold and the murder remains unsolved.

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Laura, who grew up down the street from Reesa and Jodie, says she’s convinced Jodie stabbed Reesa to death. She claims Jodie was the black sheep of the family and there was competition between the sisters.

“I feel that Jodie went in and killed her sister out of rage, and out of hate, and out of anger and built up emotions over the years,” Laura claims.

WATCH: Woman Describes Hearing Her Grandfather’s Screams And Learning Her Older Sister Had Been Murdered

In the video above from Monday’s episode of Dr. Phil, Laura gives multiple reasons why she is suspicious of Jodie – and Dr. Phil questions her evidence.

On Monday, Jodie, who adamantly denies any involvement in her sister’s murder, takes a polygraph exam. Will the results end the rumors once and for all? Check here to see where you can watch.

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