As the granddaughter of New York royalty, Kempner’s privileged life has been chronicled by the likes of Vogue, which featured her lavish Beverly Hills wedding to financier Ian McLean in 2018. Three years earlier, she began an eponymous fashion label with her brother Chris, inspired by the woman they call ‘Grand Nan’, about whom Diana Vreeland famously said: ‘There is no such thing as a chic American woman. The one exception is Nan Kempner.’

Recalling her grandmother’s influence, Kempner spoke in one interview of a holiday in the Bahamas with Nan, who had “this pair of Gucci by Tom Ford beaded and feathered jeans. They were the coolest things I’d ever seen. I was instantly hooked on fashion and worked towards building my career.”

It remains to be seen whether being outed as a possible founder of DeuxMoi will harm that career, or whether she will publicly distance herself from it, leaving Lovallo to take the heat (or reap the spoils). After all, while most of the account’s posts are harmless, they are all unverified, and some have attracted celebrities’ ire. While stories such as Scarlett Johansson’s marriage to comedian Colin Jost proved correct, others have been shot down by the stars themselves, including Hailey Bieber, who denied being pregnant and later announced she had worked out who DeuxMoi was. She’s far from the only one.

While researching her Vanity Fair piece, O’Connor heard about two group text-message threads, “one composed of Hollywood starlets and jet-setters and the other of New York’s fashion and media elite, trying to unmask the woman,” she says. “I think they saw it as, ‘You’re trying to figure out what I was doing on Saturday night, so I’ll figure out who you are,’” she says.  

When the DeuxMoi account began its dirt-dishing, it tapped into a very modern form of citizen journalism. “Everyone is a gossip columnist now, or can be,” says George Rush, a former New York Daily News reporter and co-author of Scandal: A Manual. “No celebrity is safe because everybody has been deputised to be on the lookout for them, and they have the tools to make that information public. People find it fun.”

Still, such is DeuxMoi’s power that restaurants it mentions as being frequented by stars – such as Carbone, an Italian favourite of Rihanna and Leonardo DiCaprio – immediately become the place to dine (and impossible to get a table.) Those who do get in report back on what, and who, they’ve witnessed. Rush says that the account’s ‘blind items’, which invite the reader to guess who a story refers to, are another draw, “because people see the celebrities they want to in them.” He believes one of DeuxMoi’s biggest attractions is that its stories only appear for 24 hours, then vanish. “It lures people back every day for more,” he says.

Perhaps the closest British equivalent is Popbitch, a much-loved weekly email newsletter filled with irreverent snippets about our own titans of popular culture – the difference being that, in keeping with our puerile national sense of humour, you’re more likely to find blind items about the lavatory habits of a daytime TV host than the sex life of an A-lister.

Feldman says the purpose of his investigation was not to damage DeuxMoi’s brand. “But the anonymity of the account was part of its appeal and something they were trading on,” he says. “It’s tough to square someone wanting to maintain that anonymity with the sort of growth they are pursuing, with podcasts, a book and TV deal, particularly when their line of work is about posting other people’s private information online.”

In other words, concealing your own identity while dishing up others’ secrets could be viewed as somewhat hypocritical. But neither Rush nor Feldman thinks the reported unmasking of Kempner and Lovallo – neither of whom have commented on Feldman’s claims – will diminish DeuxMoi’s popularity among fans.

“People like the idea there’s some kind of puppet master behind the scenes, but I don’t think their identity is particularly important,” says Feldman. “They still love all the blind items, even though a lot are made up or fake. They want to believe them.”

At the end of Gossip Girl, the author is revealed and forgiven (spoiler alert: it’s a man). But whether New York’s real-life elite will be so kind, only time will tell.