Ladies Of London Star & McQueen Muse Annabelle Neilson Dead At 49

Update: According to tabloid Radar Online, Scotland Yard (London's version of the NYPD) has yet to confirm the cause of death, though a spokeswoman from the Westminster Coroner's Court says Annabelle Neilson's passing is currently believed to be related to a stroke.

Her longtime friend Kate Moss posted an Instagram tribute to Neilson, on Tuesday, captioned with a broken heart emoji.

On Monday, People magazine confirmed Ladies of London star and former model Annabelle Neilson has died. She was 49.

The British socialite was last seen at the wedding of her ex-boyfriend Edward Spencer Churchill, the Duke of Marlborough's half-brother, on July 8. Her body was reportedly found in her Chelsea, London apartment on Thursday, July 12. Her cause of death, at the time of publishing, remains unknown.

Before reality television, Neilson walked the runways alongside pals Kate Moss and Naomi Campbell during the heyday of her best friend, the late designer Lee 'Alexander' McQueen. Of her relationship to McQueen (to which she was his muse), Neilson told the Daily Mail in 2015, "He was my brother, my boyfriend, my soulmate. Most of the time people called me Mrs. McQueen." Her last reflections on her closest confidant can be heard in McQueen (out July 20), the long-awaited documentary on the legendary designer who committed suicide in 2010.

Neilson's time on the Ladies of London saw her promoting her series of children's books, The Me Me Me's, which chronicled the rollercoaster of human emotions, like Dreamy Me or Angry Me, with the goal of helping children get in touch with their feelings. Her role on the show may not have included the most drama, but her reaction to it — which was more reclusive than the reality franchise may call for — made her the most level-headed of the Ladies. Neilson spoke about her struggles with openness on the show.

From 1994 to 1997, Neilson was married to billionaire heir Nathaniel Rothschild. Their marriage, though brief, was wrought with unflattering tabloid headlines. Neilson was the daughter of Marquesa Campus di Santinelli, which saw her a gilded childhood. Her cousin was the Earl of Warwick and her paternal grandmother was the second cousin of the late Queen Mother. By the age of 16, Neilson had developed a heroin addiction, which she says saved her, "because otherwise I would have killed myself."