Kellie Cooke says after she broke up with her ex and father to two of her children, she became good friends with his new wife, Tara Lambert. She says she and Lambert spent a lot of time together and co-parented her daughters.

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However, on July 28, 2015, Lambert was arrested in a murder-for-hire plot in which Cooke was the target. So how did the women go from being best friends to Lambert wanting Cooke dead?

“I think she wanted my kids,” Cooke tells Dr. Phil in an interview airing Monday. “She would call them her girls. She would make them call her Mom out in public. She couldn’t have kids at the time.”

WATCH: Did Former Model Convicted Of Hiring A Hitman Truly Want Her Best Friend Dead?

Hear more in the video above. And on Monday, Cooke, and the woman enlisted to help Lambert find a hit man, sit down together for the first time in an exclusive interview to tell their stories. And, Dr. Phil speaks with Lambert in an exclusive interview. Then, on Tuesday, see video of the undercover police sting in which Lambert was laughing as she arranged to have Cooke killed -- which led to her arrest and eventual pleading guilty. Check here to see where you can watch.

Woman Who Tara Lambert Called To Help Her Hire A Hitman Speaks Out