Socialite and aristocrat Annabelle Neilson has died at the age of 49.
The details of her death are unknown at this time.
The former model was last pictured on July 8 at the wedding Edward Spencer Churchill, the Duke of Malborough's half-brother.
Annabelle was once dubbed the 'wild child' of her wealthy family and was most famous for being the muse of late fashion designer Alexander McQueen, who she met at the age of 22.
She was also believed to be the last person to see him alive.
The former model told the Daily Mail in 2015: “He was my brother, my boyfriend, my soulmate.
"Most of the time people called me Mrs McQueen. Quite often we were sharing a bed."
Annabelle was also close friends with Kate Moss and Sadie Frost and became a member of the infamous Primrose Hill set in the 1990s.
And starred in Bravo's UK version of hit franchise Real Housewives - Ladies of London.
In 1994 Annabelle made headlines when she eloped to Las Vegas to marry millionaire banker Nat Rothschild.
A close family friend told the Mail Online at the time that Rothschild's parents were 'appalled' by their antics.
But after three years of marriage the couple split, with Annabelle reported to have received a hefty financial settlement in the divorce.
Rothschild went on to date Natalie Portman and later Ivanka Trump.
While thanks to her connections, Annabelle landed a role in US reality show Ladies of London in 2014, which she starred in for two seasons.
In 2015 she released children's book The Me Me Me’s: Angry Me.
Her last Instagram snap, posted just weeks before her death, shows Annabelle enjoying her jet-setting lifestyle as she posed in her swimsuit by a pool in Spain.
"In Spain catching some rays #sun," she told her followers.
