A new book alleges that Donald Trump repeatedly referred to MSNBC host Katy Tur using a transphobic slur during the 2016 campaign.

In Sinking in the Swamp: How Trump’s Minions and Misfits Poisoned Washington, Daily Beast journalists Lachlan Markay and Asawin Suebsaeng allege that Trump would refer to Tur — then a reporter for NBC News — as “that bitch with the tranny dad.”

Trump was reportedly referencing Tur’s biological father Zoey Tur, an award-winning journalist who came out as transgender in 2013.

Zoey Tur made history in 2015 when she became the first transgender person to be a national news reporter, after returning to work with CBS’s Inside Edition following her transition.

But none of this mattered to Trump, who seemingly reduced Zoey Tur to a single slur because of Katy Tur’s reporting during the 2016 campaign.

In an excerpt of the book, Markay and Suebsaeng chart Trump’s growing dislike for Tur, after she interviewed him in 2015 shortly after he announced his campaign.

Tur pushed back on Trump’s foreign policy claims and racist statements, which led the future president to call her “a very naive person.”

He then called Tur “Little Katy and a “third-rate journalist” during campaign rallies, and included her when branding the media “scum.”

But in private, he allegedly went even further. “To friends and advisers, he’d bitterly refer to the NBC News reporter simply as ‘That bitch with the tranny dad,'” Markay and Suebsaeng write.

Of Zoey Tur, they note that she called Trump a “fascist” and “mentally ill” in an interview with the Hollywood Reporter during the campaign.

“None of this went unnoticed by said ‘fascist,’ who held all of it against the Tur family,” Markay and Suebsaeng write.

“Ever since the days of the 2016 race, [Zoey Tur] will forever be known in President Trump’s mind as that ‘tranny’ with the ‘bitch’ kid who annoyed the billionaire demagogue so frequently during his big, loud run for office.”

Sinking in the Swamp will be released on Feb. 11 by Viking, an imprint of Penguin Publishing Group.

It is described as an “eyewitness account of Donald Trump’s clown car of lieutenants and lackeys who have polluted the corridors of power with their unprecedented awfulness.”

Related:

Elizabeth Warren will reverse Trump’s “shameful” trans military ban on first day of her presidency

Trump administration tells Supreme Court to make discriminating against trans people legal

Trump tries to justify military ban by saying transgender people take “massive amounts of drugs”

Read more:

Virginia House passes bill banning conversion therapy for minors

Brooklyn park will be renamed after LGBTQ icon Marsha P. Johnson

Pete Buttigieg makes history as first openly gay person to run in Iowa Democratic Caucuses