President Donald Trump's family has gone to court to try to block publication of his niece's book about him, her publisher and her lawyer confirmed to NBC News.
"President Trump and his siblings are seeking to suppress a book that will discuss matters of utmost public importance. They are pursuing this unlawful prior restraint because they do not want the public to know the truth. The courts will not tolerate this brazen violation of the First Amendment," Ted Boutros, a lawyer for Trump's niece, Mary Trump, said in a statement Tuesday.
The family's legal action was first reported by The New York Times. The paper cited an unidentified person familiar with the matter as saying the president's younger brother, Robert Trump, had filed for a temporary restraining order against Mary Trump in Queens Surrogate's Court, which handles will disputes.
NBC News has not obtained the legal filing.
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Mary Trump and her brother, Fred Trump III, were involved in a messy court fight over their grandfather's estate in 2000, the New York Daily News reported at the time. Mary and Fred's father, Fred Trump Jr., had died in 1984, and they said they had been shortchanged in his will thanks to the family's machinations.
The court fight included allegations that Donald Trump and his two surviving siblings cut off family medical coverage for Mary and her brother, who was married and had a young child with a neurological disorder.
"When he sued us, we said, 'Why should we give him medical coverage?'" Donald Trump told the newspaper then, referring to Fred Trump III.
The dispute was settled in a confidential agreement, which the president said last weekend included a "very powerful" nondisclosure agreement.
"She's not allowed to write a book," Trump told Axios in an interview. "You know, when we settled with her and her brother, who I do have a good relationship with — she's got a brother, Fred, who I do have a good relationship with — but when we settled, she has a total ... signed a nondisclosure."
"It covers everything," the president added.
Mary Trump's book, "Too Much and Never Enough: How My Family Created the World's Most Dangerous Man," is scheduled to be released July 28. Publisher Simon & Schuster describes the book as a "revelatory, authoritative portrait of Donald J. Trump and the toxic family that made him."
"She describes a nightmare of traumas, destructive relationships, and a tragic combination of neglect and abuse. She explains how specific events and general family patterns created the damaged man who currently occupies the Oval Office, including the strange and harmful relationship between Fred Trump and his two oldest sons, Fred Jr. and Donald," the description says.
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In a statement to The Times, Robert Trump said that he was "deeply disappointed" in his niece and that her "attempt to sensationalize and mischaracterize our family relationship after all of these years for her own financial gain is both a travesty and injustice to the memory of my late brother, Fred, and our beloved parents."
Simon & Schuster, which on Tuesday released another book the president had tried to stop, John Bolton's "The Room Where It Happened," predicted that it would have similar success publishing Mary Trump's book.
"As the plaintiff and his attorney well know, the courts take a dim view of prior restraint, and this attempt to block publication will meet the same fate as those that have gone before," the company said in a statement.