British model and former reality show star Annabelle Neilson has passed away at the age of 49 on 12 July. The cause behind her death is currently unclear, with few details available. The 'Ladies of London' star was not known to have been suffering from any ailments. 

Neilson was the daughter of Elizabeth, the Marquesa Campus di Santinelli, her first cousin was the Earl of Warwick and her paternal grandmother was the second cousin of the late Queen Elizabeth I, The Queen Mother. 

Neilson passed away today at the age of 49. (Source: Anthony Harvey/Getty Images)
Neilson passed away today at the age of 49. (Source: Anthony Harvey/Getty Images)

The aristocratic lineage also meant that her childhood was a privileged one. According to the Daily Mail, as a young girl, she enjoyed playdates at the Warwick Castle which almost a millennium old. She also split time between her family's country estate in the Chilterns and West London.

She married financier Nat Rothschild, the heir to the title of Baron Rothschild, currently held by his father Jacob Rothschild, and heir apparent to a fortune of £500 million. The pair reportedly met on a beach in India and went on to tie the knot in 1994. However, the marriage was short-lived, ending in divorce and a messy settlement in 1997 that saw Neilson paying a handsome sum to sign a confidentiality agreement and rescind her ex-husband's dynastic name.

One of the reasons the marriage supposedly broke apart was Neilson's penchant for partying, a fact that had become an open secret in the early 1990s. When she was 22, she had been introduced to fashion designer Alexander McQueen through late Tatler fashion editor Isabella Blow, and the pair instantly hit it off.

The designer hung himself in 2010 and Neilson was said to be the last person to have seen him alive. Unsurprisingly, considering the pair's close relationship, it hit her harder than most. She told the Mail in an interview that they were "so alike," adding, "He was also dyslexic; he mirrored me in so many ways." She confessed that he had asked her to marry him but that she had refused. 

It was also through McQueen that she came in contact with fellow models Kate Moss and Naomi Campbell, growing incredibly close with both. The trio then became a part of the now infamous Primrose Hill set where all-night drug-addled parties at Noel Gallagher and Meg Mathews' Supernova Heights mansion were commonplace, earning Neilson her reputation as a 'wild child.'

It seemed as though she had left those days behind when she began dating Edward Spencer Churchill, the Duke of Marlborough's half-brother. But the pair soon broke up, though they did continue to remain close. In fact, she was at his marriage held at the Blenheim Palace in Woodstock, Oxfordshire, as late as last week.