One month after Joe Biden announced his run for president, several Fox News stars have already begun quietly pushing rumors that the 76-year-old ex-veep is in poor health.

Since the end of May, Fox Business Network and Fox News star Lisa “Kennedy” Montgomery and Fox News prime-time host Sean Hannity have speculated on-air, on at least four separate occasions, that the current Democratic presidential frontrunner is secretly dealing with health issues, often comparing his condition to illness-related conspiracy theories the network pushed about Hillary Clinton during the 2016 election.

The Biden rumor-mongering seemingly began May 29, during the broadcast of Fox News’ afternoon gabfest The Five. While assessing Biden’s candidacy, Kennedy claimed to know Democratic operatives engaged in a whisper campaign about Biden’s health.

“He is much more like Hillary Clinton, because if you talk to Democrats, who are working for different campaigns, all of the aggressive gossip whisperers—and this is where the action is happening in terms of opposition research—it’s people having a few drinks at a bar and whispering, ‘You know there is something wrong with the former vice president,’” she claimed. “But that’s what they are actively doing right now. And it is surprising because they are concerned with taking Biden down and getting their candidate out there.”

Co-host Jesse Watters, an avid Trump booster, pressed Kennedy to elaborate. “Don’t do it,” co-host Greg Gutfeld joked to Kennedy, acknowledging the danger in openly speculating about Biden being sick.

The innuendo seemed to go over the head of Watters, however, as he took it upon himself to explain “the gossip” about Biden as involving his support from black voters. Gutfeld laughed, remarking: “I don’t think that’s what Kennedy meant.”

“I was thinking more along the lines of Hillary Clinton having a lumpy overcoat in 85-degree weather,” Kennedy explained, invoking a popular 2016 right-wing conspiracy theory fixated on a photo of Clinton wearing a wool jacket with a lump on the back while campaigning in warm weather.

“He looks healthy to me,” Watters—surprisingly—replied.

In the news business, it is considered irresponsible to spread baseless, potentially damaging rumors about public figures. Even Fox News briefly suspended Judge Andrew Napolitano in early 2017 after he made the unfounded claim on-air that British officials helped President Obama spy on the Trump campaign. Beyond news personalities, the American Medical Association considers it wholly unethical for physicians to speculate on public officials’ health without having personally examined them.

Nevertheless, early last week, while hosting her eponymous Fox Business Network show, Kennedy suggested Biden’s campaign staff may want to keep him “off a main stage” because he says “stupid things and he slurs,” adding that Biden “does look very tired.”

The following evening on her program, Kennedy went even further, once again invoking the conspiracy theory about Clinton’s overcoat to suggest Biden could be viewed as being in poor health.

“I think that it is a good move on Bernie’s part comparing Joe Biden to Hillary,” she said about Sanders saying that, in possibly picking Biden, Democrats might make “the same mistake” they did in nominating Clinton in 2016.

Sanders was referring specifically to how, in his estimation, there was and is a lack of energy and enthusiasm around both “establishment” candidates. And yet Kennedy suggested the comparison was health-related. “The more damage that [comparison] does, you go, ‘You know we haven’t seen Joe a lot, maybe he has hidden health issues, is always wearing an overcoat.’”

That same evening, during his top-rated prime-time Fox News show, Hannity—who regularly echoes Trump in calling the former vice president “Sleepy Joe”—also referenced Clinton to speculate about Biden’s health.

“Joe Biden’s tired,” he declared. “He does not have the energy for this. He’s not up for this challenge. They’re already hiding him like they hid Hillary. They don’t want him out there.”

In a statement to The Daily Beast, the Biden campaign’s national press secretary, TJ Ducklo, said “These are baseless lies meant to stoke fear in their viewers. It has no place in our public discourse, and anyone amplifying it bears some responsibility for giving it legitimacy it most certainly does not deserve.”

But this not the first time cable-news stars have made similar unverified insinuations about a candidate.

In the summer of 2016, Fox News devoted copious amounts of airtime to conspiracy theories about Hillary Clinton’s medical state. For an entire week in August, Hannity hosted segments in which he and a slew of guests analyzed out-of-context photos and videos while referencing Clinton’s 2012 concussion to claim the Democratic nominee was battling chronic illnesses, maladies, seizures, and critical neurological conditions. It didn’t take long for the Trump campaign to echo the claims.

At the time, even Newt Gingrich noted the recklessness in baselessly speculating about public figures’ health issues, calling it “junk medicine.” Additionally, he fretted: “Next you’re gonna get a left-wing psychiatrist explaining Donald Trump in negative terms."

And now since taking office, Trump himself has occasionally been the butt of such illness-related speculation.

CNN senior media correspondent Brian Stelter faced criticism when he wondered aloud in 2017 why more journalists don’t ask “uncomfortable questions” about the president’s mental state. “His actions have been described as unpresidential, unhinged, and sometimes even crazy,” Stelter said. “That word crazy can be interpreted several different ways. It gets said more in private than on TV.” And Stelter has been far from alone at CNN when it comes to questioning the president’s mental fitness.

MSNBC hosts, too, have speculated on the president’s mental and physical fitness. For example, for more than a year now, Trump’s ex-pal-turned-nemesis Joe Scarborough has repeatedly claimed the president is dealing with neurocognitive disorders.

In November 2017, the Morning Joe host relayed that “people close to him during the campaign told me he had early stages of dementia.”

In recent weeks, Scarborough has resuscitated these rumors, insisting last month that those who know Trump are worried that he has “pre-dementia” and is in “mental decline.”

—With additional reporting from Andrew Kirell.