Mary Trump, President Trump’s niece, will publish a book this summer that will contain “harrowing and salacious” information about her uncle, the Daily Beast reports.

Simon Schuster is set to publish Too Much and Never Enough, in which Mary Trump reveals that she provided tax documents involving President Trump to the New York Times. The Times declined to comment to one of its own reporters on that revelation.

The Daily Beast reports that the book will also feature “intimate and damning” comments about President Trump from his sister, Maryanne Trump Barry, a former federal judge who was appointed to her post by President Clinton.

Barry resigned from the bench last year after the Times printed a report that alleged she was involved in a series of tax schemes involving President Trump that enriched their family.

Mary Trump will also write about her father, Fred Trump Jr., who died at 42 after a long struggle with alcoholism. Mary Trump will allege that “Donald and Fred Trump Sr. contributed to his death and neglected him at critical stages of his addiction,” according to the Daily Beast.

Mary Trump’s book has the potential to be the most explosive book about the president to date. News of the book comes just days after President Trump’s former national security advisor, John Bolton, said that he still intends to publish his own book later this month despite objections from the White House.

Too Much and Never Enough is slated for publication on Aug. 11.

Michael Schaub is a Texas-based journalist and regular contributor to NPR.