The relationship between the Bidens and Vice President Kamala Harris purportedly became messy after Harris -- then Joe Biden’s opponent in the primary -- came after him for his record on busing and his boasts of his relationships with segregationist senators, according to journalist Edward Isaac Dovere. 

First lady Jill Biden even said Harris can "go f--- herself" in a call with campaign donors, Dovere writes in his forthcoming book shared with Fox News, "Battle for the Soul," to be published May 25. 

It was after Joe Biden had reminisced in a speech on his early days in Washington, trying to emphasize his record as a deal broker, Dovere writes. He talked about his relationship with two holdout segregationists in the Senate.  

"Well, guess what? At least there was some civility. We got things done," Joe Biden said at the time. "We didn’t agree on much of anything. We got things done. We got it finished. But today, you look at the other side and you’re the enemy. Not the opposition, the enemy. We don't talk to each other anymore."

"I was in a caucus with James O. Eastland," Joe Biden said as he briefly imitated the late senator’s southern drawl in July 2019.  "He never called me boy. He always called me son."

"If the people he was talking about with such affection had their way, I would never have been able to be a United States senator," Harris said to reporters two days after the debate in South Carolina.

Harris’ team told the then-candidate she "had to land hard on Biden" in the next debate, Dovere writes. Harris was apparently reluctant, as she’d developed a close relationship with the Biden family.

WHY HARRIS IS TREADING CAREFULLY IN BIDEN WORLD 

"She was searching for some way to condemn him for what he had said and done without attacking the man she liked and respected," according to the book. 

"I’m going to now direct this at Vice President Biden: I do not believe you are a racist, and I agree with you when you commit yourself to the importance of finding common ground," she said at the June 2019 debate. 

"But I also believe, and it’s personal – it was hurtful to hear you talk about the reputations of two United States senators who built their reputations and career on the segregation of race in this country. And it was not only that, but you also worked with them to oppose busing. And, you know, there was a little girl in California who was part of the second class to integrate her public schools, and she was bused to school every day. And that little girl was me," Harris continued in a zealous moment that went viral and raised the then-California senator’s poll numbers significantly, if only for a brief period. 

BIDEN HITS A ROUGH PATCH AS REPUBLICANS TRY TO BLAME HIM FOR EVERYTHING

Joe Biden had leaned over to fellow Democratic candidate Pete Buttigieg during a commercial break. 

"That was some f---ing bullsh--," he said, Dovere writes, citing multiple people to whom the conversation was relayed afterward. 

Asked about Harris’ rising poll numbers, Biden told reporters sarcastically at the time: "I was probably overly polite in the way I didn’t respond to an attack, ‘You’re not a racist’ – which is a nice thing to say, really reassuring."

"With what he cares about, what he fights for, what he’s committed to, you get up there and call him a racist without basis?" Jill Biden reportedly said of Harris on a phone call with close supporters a week later. "Go f--- yourself." 

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Dovere reported that, in reality, Biden and Harris had basically the same position on busing, or the forced integration of schools, a policy that hadn't been a central debate in nearly 50 years: Both supported voluntary busing but opposed federally mandated busing unless local governments stood in the way.