The clinical psychologist slammed her relative in the latest edition of her Substack newsletter while responding to Sen. Ted Cruz’s (R-Texas) questioning of the masculinity of Texas U.S. Senate candidate James Talarico.

“Apparently we are supposed to believe Ted Cruz is now the nation’s foremost authority on masculinity,” she wrote. “Personally, I do not care. It seems like an odd qualification for public office. What are they going to do? Arm wrestle? Challenge each other to duels?”

“Fight in a cage match on the White House lawn?” she added, a sarcastic nod to the controversial UFC fight card that the president hosted on his 80th birthday on Sunday.

“But if we are defining masculinity, I would have thought one basic requirement would be defending your spouse when another man publicly attacks her,” Mary Trump continued, a nod to her uncle’s personal attacks on Cruz’s wife, Heidi, during the 2016 presidential election and the senator’s subsequent endorsement of his onetime rival.

She then delivered a pointed swipe at the president.

“What do I know?” wrote Mary Trump, a fierce critic of the president. “I grew up in a family with Donald Trump, who knows absolutely nothing about being a real man.”