Donald Trump’s niece, psychologist and author Mary Trump, is once again making headlines for her blistering commentary on the president — and this time, she’s not holding anything back.

A reign of idiocy?

President Donald Trump has long projected an image of dominance and strength —but a growing number of mental health experts say that beneath the bravado may lie something more fragile.

According to a striking analysis aired on MSNBC’s The Weekend: Primetime, Trump may be “haunted”

by the fear of facing the same cognitive decline that affected his father, Fred Trump Sr., who suffered from Alzheimer’s disease in his later years.

And now, yet another voice is joining the growing debate over Donald Trump’s mental fitness — and this one hits close to home.

Mary Trump, the president’s own niece and a trained psychologist, has long warned about her uncle’s mental and emotional state.

But in a new episode of her YouTube series Trump Trolls Trump, she takes it even further — describing his current behavior as a “reign of idiocy.”

According to Mary, her uncle is spiraling further into cognitive decline.

“We’re now 166 days into the Trump regime’s reign of terror, reign of confusion, reign of chaos, but also let’s call it what else it is, it’s a reign of idiocy,” she said.

And she didn’t stop there.

Mary, who previously authored the best-selling takedown Too Much and Never Enough: How My Family Created the World’s Most Dangerous Man, pulled no punches when speaking about Donald Trump’s mental state.

“Time flies when you’re having a horrible time and when democracy is slowly being strangled by a man who can’t tie his own shoes,” she quipped.

Took a shot at Trump’s recent public appearance

Despite the harshness of her remarks, she did — if you can call it that — acknowledge one of Trump’s rare talents: blending narcissism with cognitive dysfunction. “Donald is good at very, very few things but I’m going to give him credit for something,” she said. “He has an actually quite decent ability to mix cognitive decline with narcissism. I mean that’s a twofer.”

Mary also took a shot at Trump’s recent public appearances, including a stop at the controversial new Florida immigration facility known as Alligator Alcatraz. When asked how long detainees would be held, Trump gave a meandering response that touched on everything from New York taxes to redecorating the Oval Office.

Mary was quick to slam the bizarre response: “The question, you idiot, wasn’t do you like Florida?” she said. “The reason he can’t answer that question is because he doesn’t have an answer.”

She went on to describe the president as “increasingly far gone,” adding, “He has an attention span of a toddler, although that’s actually nothing new.”

The psychologist also voiced frustration with what she sees as Trump’s refusal to engage truthfully with the American public. “I’m sick of this thuggish lunk sitting there and denying the American people access to any truths about anything whatsoever,” she said.

And if that wasn’t enough, Mary took aim at Trump’s latest money-making scheme: a luxury fragrance. Recently unveiled on Truth Social, the Trump-branded “Victory” perfume is selling for a whopping $249 per bottle — complete with a gold figurine of the president himself.

“It is grotesque for the sitting president of the United States to grift off of his office, but here we are,” she said. She wrapped things up with a zinger: “The idea of having to guess what that horror smells like is deeply unfair to those of us who are still sane.”