Melania Trump allegedly delayed moving to the White House in 2017 because she was renegotiating her prenuptial agreement with President Donald Trump, according to a new book on the first lady.

When Trump and his family were set to move into the White House after his inauguration, Melania and her son Barron stayed behind in New York City. Reports at the time stated that Melania wanted Barron to finish his school year with his friends. But, in a new book, The Washington Post reporter Mary Jordan writes that while that might’ve been true, Melania also used this time as leverage to renegotiate her prenuptial agreement with her husband.

Jordan’s new book, titled The Art of Her Deal: The Untold Story of Melania Trump is set to be released Tuesday, and is based off of more than 100 interviews with people close to the first lady.

In the book, Jordan states that details of Trump’s affairs that were exposed during the election cycle had an effect on Melania, and she needed time away from her husband. During this time, she made sure her prenuptial agreement would allow Barron some right to Trump’s family business, like his older children have. According to the Post the book goes on to say that Melania’s original prenup was “not incredibly generous,” although Melania has been married to the president longer than his other ex-wives.

According to the Post her absence gave her negotiating power, as it became clear that her presence calmed the president. Jordan wrote that at least one of Trump’s adult children had asked Melania to come to Washington as quickly as possible.

Melania’s Chief of Staff, Stephanie Grisham, dismissed the book:

“Yet another book about Mrs. Trump with false information and sources. This book belongs in the fiction genre,” she said.