After 40 years of marriage, Hope says her grandmother, Lucy, left her husband and left town with a man named Ken, who Lucy has now been dating for a couple of years.

It just so happens that Ken used to be married to Hope’s mother Cheryl – who is Lucy’s daughter.

“It really does shock me my grandmother is with Ken,” Hope says. “And that causes a lot of family problems.”

Cheryl says she was “blindsided” by her mom’s relationship with her ex-husband, which she says she believes started roughly six months after her split from Ken.

“I had no idea that they had gotten together,” Cheryl says. “I was shocked and betrayed.”

Both Cheryl and Hope also claim that Ken was “angry” and “controlling” toward Cheryl during their marriage – and they say they fear for Lucy’s well-being.

But Lucy insists she is happy with Ken, and says her family’s unsubstantiated claims of abuse don’t ring true to her.

“Ken is not controlling or abusive at all,” Lucy says. “If my daughter says I need to choose between her and Ken, I’m going to say that I’m very happy with Ken right now, and I’m staying in this relationship.”

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“I’m very worried about my mom’s safety with Ken,” Cheryl claims.

“Ken is a very bad guy. He’s a very controlling man,” claims Hope. “I will go to the end of the world and back to get her away from him – to have my family back … I need her to leave Ken. I need her to physically push him out of her life.

“If they were to take a huge step in their relationship, he could be my grandfather – and he was already my stepdad at one point in my life,” Hope continues. “That’s pretty crazy,”

Cheryl says she even went as far as to give her mother an ultimatum.

“I will cut her out for good if she chooses him over me,” Cheryl says.

Can Dr. Phil help this family mend their wounds, or could this confrontation be the end of the debate and possibly their relationships? This episode airs Wednesday. Check here to see where you can watch.