In a new book compiled from interviews in the final six months of her life, the late first lady Barbara Bush cited "angst" brought on by then-presidential candidate Donald Trump's persistent attacks on her son Jeb during the 2016 campaign as an exacerbating factor to her congestive heart failure. In "The Matriarch: Barbara Bush and the Making of an American Dynasty," author and USA Today Washington Bureau chief Susan Page recounts Bush being rushed to the hospital in June 2016.

"The tumultuous presidential campaign in general and Trump's ridicule of son Jeb Bush in particular had riled her," Page writes. According to Page, Jeb had urged the former first lady to "let go" of her frustrations with the controversial candidate, and instead focus on herself and her health. Mr. Trump would often criticize Jeb as being "weak" and "low energy" on the campaign trail.

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"Jeb said, 'Mom, don't worry about things you can't do anything about,'" Barbara Bush told Page. "He's right. Just do good, make life better for someone else."

Over the course of the campaign, the unfiltered matriarch expressed disbelief about some of the things then-candidate Trump had said about women, not afraid to punch back at Mr. Trump's commentary of her son.

"I mean, unbelievable. I don't know how women can vote for someone who said what he said about Megyn Kelly," she said in an interview with CBS News. "And we knew what he meant too!"

Despite Bush saying in 2013 that the country had "had enough Bushes", the former first lady campaigned with Jeb in 2016 in his bid for the Republican nomination. Jeb would go on to not win a single state in the 2016 primary.

But even as a lifelong devotee to the Republican party, Bush told Page in February of 2018 that she'd "probably say no today" when asked if she considered herself a member of the party in the era of Trump.

"I'm trying not to think about it," she said of the Trump presidency in an interview with Page. "We're a strong country, and I think it will all work out."

Bush, the second woman in U.S. history to be a first lady and mother of a president, died at age 92.