Mary Trump, a clinical psychologist and niece of the outgoing US President Donald Trump, said a 'grim' future is waiting for him as he tries to 'change the narrative' around his legacy while facing a loss of relevance and legal threats.
Trump's last day in office was 'probably the worst day of his life', she told CNN on Tuesday.
Trump will leave the White House early on Wednesday and President-elect Joe Biden will be sworn in on Tuesday.
"This is probably the worst day of his life, because the clock is ticking and he's running out of time," Mary Trump, who wrote a book about her uncle, told CNN's Anderson Cooper on Tuesday.
"The other thing I just want to point out about that speech, it was reminiscent of a video he made after the insurrection saying the movement is just beginning, which seems like a bit of a threat to me," Trump said, comparing the video farewell message from the president to one before the siege of the Capitol building two weeks ago.
"My hope is that he be as contained as possible. He's going to do whatever he can or believes he can to change the narrative and I think we're going to see that play out with some of these pardons in excess of 100, if I'm hearing that correctly, and some of these pardons will be quite horrific, some of them will be strategic."
"But the bottom line is he's out of there. I mean, he's been out of there, you know, metaphorically speaking, for a long time. He's not been doing the job.
"As of 12 o'clock or earlier, he's heading down to Florida and he no longer has powers and protections of the Oval Office, and he knows it," Mary Trump said.
Trump's departure from office comes just two weeks after his supporters stormed the Capitol building, killing a police officer while vandalising and looting the home of Congress.
The outgoing president was impeached a week later for a record second time over allegations that he incited the riot. He will face a trial some time after Biden takes office.
If convicted, Trump would be barred for life from holding public office, however it remains unclear whether Republicans senators will vote to convict.
Since the riot, Trump has been laying relatively low, with a ban from most social networks including Twitter blocking his preferred means of communication.
However in his final hours in office on Tuesday he issued 73 pardons, most notably to his former adviser Steve Bannon who is facing fraud charges and to the rapper Lil Wayne, who pleaded guilty to a federal weapons charge last year.
Trump also commuted the sentences of another 70 people including Kwame Kilpatrick, who was sentenced to 28 years in prison in 2013 on racketeering, bribery and extortion charges.
The charges relate to Kilpatrick's time as mayor of Detroit, the subject of the second season of the popular podcast Crimetown.
It is not clear how Trump plans to spend his time after leaving office but he has expressed his desire to make his permanent home at his Mar-al-Lago property.