Washington CNN  — 

As his eldest son faced the prospect of resigning as Delaware’s attorney general amid health concerns, Vice President Joe Biden received an offer that floored him: financial support from his boss, President Barack Obama.

In the never been told before story, Biden recalled how concerned Obama had been.

Describing in an interview with CNN chief political analyst Gloria Borger one of his weekly lunches with Obama, Biden said he told the President he was worried about caring for Beau’s family without his son’s salary.

“I said, ‘But I worked it out.’” Biden recalled telling Obama. “I said, ‘But – Jill and I will sell the house and be in good shape.’”

Obama, Biden remembered, pushed back vehemently on the thought of Biden and his wife selling their home in Wilmington, Delaware.

“He got up and he said, ‘Don’t sell that house. Promise me you won’t sell the house,’” Biden continued, speculating Obama would be “mad” he was retelling the story.

“He said, ‘I’ll give you the money. Whatever you need, I’ll give you the money. Don’t, Joe – promise me. Promise me.’ I said, ‘I don’t think we’re going to have to anyway.’ He said, ‘promise me,’” Biden recalled.

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Beau Biden, after tests showing he lost no cognitive ability after his stroke, served out his second term as Delaware’s attorney general. After leaving office in January 2015, however, he grew ill with brain cancer. Beau Biden died in last May.

When asked about the incident, White House press secretary Josh Earnest said it was a sign of how the two have “legitimately become good friends.”

“Obviously, the President and the vice president have developed the kind of personal relationship that just transcends their professional responsibilities,” Earnest told CNN’s “New Day” on Tuesday, citing Obama’s eulogy at Beau Biden’s funeral as another example of their close bond.

“Thanksgiving was hard,” the vice president acknowledged during the interview Monday, saying his family forged on during a wrenching holiday period.

“The idea of an empty chair, you know, was something no one looked forward to,” he said. “But everybody – you know, they’re tough. And you know, we’re focusing on the inspiration of Beau, rather than loss of Beau.”

That includes Obama, who Biden said experienced Beau’s loss as more than just a boss or a friend.

“It’s personal,” Biden said. “It’s family.”