Two Trump family members got “inappropriately – and perhaps dangerously – close” to agents protecting them while Donald Trump was president, according to a new book on the US Secret Service. Zero Fail: The Rise and Fall of the Secret Service, by the Washington Post reporter Carol Leonnig, is published next week. The Guardian obtained a copy. Leonnig won a Pulitzer prize in 2015, for her reporting on security failures at the Secret Service. She was also part of the Post team which won a Pulitzer for its work on Edward Snowden’s leaks about National Security Agency surveillance techniques and reported extensively on Russian election interference and links between Trump and Moscow. She has also won three Polk awards. With Philip Rucker, Leonnig also co-authored A Very Stable Genius: Donald J Trump’s Testing of America, a well-received 2020 White House exposé. In her new book, she writes that Secret Service agents reported that Vanessa Trump, the wife of the president’s oldest son, Donald Trump Jr, “started dating one of the agents who had been assigned to her family”. Vanessa Trump filed for an uncontested divorce in March 2018. Leonnig reports that the agent concerned did not face disciplinary action as neither he nor the agency were official guardians of Vanessa Trump at that point. Leonnig also writes that Tiffany Trump, Donald Trump’s daughter with his second wife, Marla Maples, broke up with a boyfriend and “began spending an unusual amount of time alone with a Secret Service agent on her detail”. Secret Service leaders, the book says, “became concerned at how close Tiffany appeared to be getting to the tall, dark and handsome agent”. Agents are prohibited from forming personal relationships with those they protect, out of concern that such feelings could cloud their judgment. Both Tiffany Trump and the agent said nothing untoward was happening, Leonnig writes, and pointed out the nature of the agent’s job meant spending time alone with his charge. The agent was subsequently reassigned. Leonnig also reports that it was not clear if Donald Trump knew what Secret Service personnel were saying about his daughter and daughter-in-law. But she says the president did repeatedly seek to remove Secret Service staff he deemed to be overweight or too short for the job. “I want these fat guys off my detail,” Trump is reported to have said, possibly confusing office-based personnel with active agents. “How are they going to protect me and my family if they can’t run down the street?”