The ex-president’s niece is “fairly sure” her cousins will also flip on their father.
"He is a physical coward but he’s perfectly happy when other people commit violence on his behalf," said the president's niece.
"Donald has never been in this place before where there's nobody to bail him out, there's nobody to buy him out."
The president's niece told CNN's Don Lemon that Trump would be in for a "rough ride."
Trump's debate message was more than just a shoutout to hate groups, the president's niece warned.
The ruling will allow Mary Trump to publicise her book about the president when it hits stores on Tuesday.
Donald Trump's niece alleges in her upcoming book that her uncle cheated his way into college and commented on her breasts.