President Trump's niece after slamming him in a tell-all book is taking him to court.

Mary Trump, the president's niece who spoke out against him as she published the book Too Much and Never Enough: How My Family Created the World's Most Dangerous Man in July, on Thursday filed a lawsuit against him in New York, accusing the president and his siblings of fraud, NBC News reports.

The lawsuit claims that for president, his sister Maryanne Trump Barry, and his late brother Robert Trump, "fraud was not just the family business — it was a way of life," and it accuses them of having "concocted scheme after scheme to cheat on their taxes, swindle their business partners, and jack up rents on their low income tenants."

Mary Trump also claims in the lawsuit that after the death of her father, Fred Trump Jr., the president and his siblings "fleeced her of tens of millions of dollars" of her inheritance after they "designed and carried out a complex scheme to siphon funds away from her interests, conceal their grift, and deceive her about the true value of what she had inherited," per NBC.

President Trump previously attacked his niece after the publication of her tell-all book, calling her a "seldom seen niece who knows little about me," and the White House called Too Much and Never Enough a "book of falsehoods." White House Press Secretary Kayleigh McEnany also said Thursday that "the only fraud committed there was Mary Trump recording one of her relatives," referring to Mary Trump having secretly recorded conversations with Maryanne Trump Barry.

Mary Trump in a statement on Thursday alleged Trump and his siblings "betrayed me by working together in secret to steal from me" and said she's bringing the lawsuit "to hold them accountable and to recover what is rightfully mine." Brendan Morrow