Shelby’s sister, Kelsey, died of a drug overdose in 2011 when Shelby was just 15. She says she saw Kelsey passed out in her bedroom on the night in question, but didn’t realize she needed help. Shelby says she believes her oldest sister, Shayne, blames her for Kelsey’s death.

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“I don’t blame Shelby,” insists Shayne, adding, “I just want somebody to blame.”

WATCH: ‘My Life Has Become Unmanageable,’ Admits Self-Described Heroin Addict

In the video above, the sisters discuss the circumstances surrounding Kelsey’s death, and why Shayne says she keeps envisioning how Shelby might have stepped in to prevent it.

Watch the conclusion of this two-part Dr. Phil airing Tuesday. Check here to find your local listing.

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