Jared Kushner, Donald Trump’s Jewish son-in-law and increasingly a power player atop his presidential campaign, was an obvious choice to publicly defend the candidate this week amid a firestorm over a tweet that many viewed as anti-Semitic. But now he's under fire from his own relatives, who are angry he invoked their grandparents' story of survival during the Holocaust in an attempt to defend Trump.

The tweet, which Trump heartily defended during a rally in Cincinnati on Wednesday night even after Kushner’s efforts to quell the uproar, featured an image of Hillary Clinton over a backdrop of dollar bills. Inside a red, six-pointed Star of David, white text labeled Clinton the “most corrupt candidate ever.”

Kushner, Ivanka Trump's husband, attempted to defend his father-in-law from what the campaign says is a journalistic mob driven by political correctness. In a piece published Wednesday, Kushner revealed his grandparents' story of survival during World War II because, he wrote, “it’s important to me that people understand where I’m coming from when I report that I know the difference between actual, dangerous intolerance versus these labels that get tossed around in an effort to score political points.”

But Kushner’s estranged relatives are angry about his decision to invoke their grandparents’ story as Holocaust survivors — and they let it be known on social media, complete with a few typos.

“I have a different take­away from my Grandparents' experience in the war,” Marc Kushner, a New York City-based architect and first cousin, wrote in a Facebook post Thursday morning with a link to his cousin’s Op-Ed. “It is our responsibility as the next generation to speak up against hate. Anti­semitism or otherwise.”

He also posted a link to a piece by Dana Schwartz, a Jewish woman who works for Jared Kushner at the New York Observer and who asked him point blank: “[H]ow do you allow this?”

Jacob Schulder, another cousin, went even further in a comment on Marc Kushner’s post, writing: “When an out of touch with reality nominee hires an out of touch with reality campaign manager, who is also a son­-in-­law, you get the BS Jared wrote. I don't think Trump is an anti­Semite; I think he's a lying idiot (among other things) with little to no experiences outside his teetering fiefdom of failed development projects, divorces, bankrupted sports leagues, fraudulent 'Universities' and golf courses (and the list keeps going). The very first thing a responsible campaign manager should do, I'd think, and I mean the very first thing, would be to take away his father-­in­-law's Twitter account. Even Joseph Kushner would've had the street smarts to figure that one out while living on boiled potatoes in the forest.”

He continued: “That my grandparents have been dragged into this is a shame. Thank you Jared for using something sacred and special to the descendants of Joe and Rae Kushner to validate the sloppy manner in which you've handled this campaign. From the references to 'Palestine' at the AIPAC conference (which got Donald jeered) to the justification of the itchy Twitter fingers your father­in­law has, you've managed to further prove what so many of us have known for many years. Kudos to you for having gone this far; no one expected this. But for the sake of the family name, which may have no meaning to you but still has meaning to others, please don't invoke our grandparents in vain just so you can sleep better at night. It is self serving and disgusting.”

This family spat is part of an ongoing family feud that dates back to the case that put Jared Kushner's father in jail 10 years ago. In fact, the parents of both Marc Kushner and Jacob Schulder were corroborating witnesses for the government—in a case prosecuted by Chris Christie, the former U.S. attorney for New Jersey who is now a top Trump campaign adviser—in that case against Charlie Kushner, Jared's father and a Manhattan real estate tycoon, who was sent to prison in 2005 for tax evasion, witness tampering and illegal campaign contributions. 

"Jared hasn't spoken to either of these people in 10 years," one source close to Kushner told POLITICO Thursday afternoon.

Jared Kushner and the Trump campaign did not immediately respond to requests for comment.