'Achilles' heel': Mary Trump says her uncle's 'swagger has spelled disaster for his case'

Donald Trump's crowd envy and superpower flexing are digging him into a deep legal hole, his niece warned.

Mary Trump has been unsparing with her jabs at her notorious uncle and, in a recent edition of her Substack podcast "The Good In Us," she talks about his bravado backfiring.

"Donald’s penchant for baseless swagger has spelled disaster for his case," she said, specifically aiming at the federal case in Washington, D.C., in which the former president is accused of committing four federal felonies in connection with his attempt to cling to the presidency after suffering a 2020 election loss.

"You might think Donald will never be held accountable. But I know Donald personally."

"And I can tell you his Achilles' heel – his pathetically inflated sense of himself."

In a recorded sidebar chat with ABC News reporter Jonathan Karl, author of Tired Of Winning, Trump brags about the number of his supporters filled into the city for the "Stop The Steal" protest where he delivered a speech back on Jan. 6, 2021.

It ended in a deadly riot where mobs charged the Capitol building, stalling Congress's certification of the election results.

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“If you look at the real size of that crowd, it was never reported correctly,'" Trump told Karl. "There were — it's the biggest crowd I've ever spoken in front of by far. By far."

Then he talked about how he could have used his sway to quit the "Stop the Steal" siege.

“I was thinking about going back during the problem to stop the problem, doing it myself," he said. "Secret Service didn't like that idea too much."

She said that "the fact that he's recorded saying, basically, ‘I knew that these were my supporters — they were there to do what I wanted them to do, to stop the certification’ is good evidence of his participation."

The conspiracy component is strengthened more and more as evidence of Trump waxing about the fateful day piles up to the point that Mary Trump believes the federal prosecutor in the subversion case, Jack Smith, should exploit it as a "pathway to a conviction."