“I am beyond angry with my mother,” says Dana.

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Dana says that two years ago, her sister Sherri revealed that she had a different father than Dana and that their mother, Betty, had lied to Sherri her entire life about who her father was. She says the truth was uncovered when Sherri found a letter her mom had kept hidden in a Bible for more than a decade.

“My mom is still in denial about Sherri’s dad, Wayne. After pushing and prodding, she says she knows Wayne, but still had no idea he was Sherri’s father,” Dana says. “What she’s been telling us for years is just one big, fat lie.”

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Dana says it’s time her mother admit the truth. “What I want my mom to do right now is to look my sister, Sherri, in the eye and tell her she is sorry for what she has done to her. I want her to apologize and beg her for her forgiveness, and to mean it from the bottom of her heart,” Dana says.

Can this family find closure and heal their relationships? Watch what happens on Thursday's episode of Dr. Phil. Check here to see where you can tune in.

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Woman Accused Of Lying To Daughter About The Identity Of Her Father Tells Her Side of the Story