Now, a cousin of the royal who co-owns a farm (pictured) with her in Argentina has told the Daily Mail the reason Fergie went into hiding – because she was protecting her daughters

The former Duchess of York still owns a share of the isolated El Pucara, a 1000-acre ranch which is a six hour drive from Buenos Aires where her late mother Susan Barrantes lived

Fergie has long held Argentina close to her heart. It is where her mother Susan Barrantes (pictured with Fergie at Polo in Windsor in 2006) lived until her death

On the edge of the Pampas, Argentina’s famous fertile grasslands, it is an idyllic spot with miles of flat countryside devoted to crop farming, cattle ranching or stud ranches for polo horses and reachable only by driving miles along dusty unsurfaced trails.

And it has now emerged that El Pucara is jointly owned by Martin and Fergie – and although she has not visited for more than 15 years, she still keeps in regular contact with him, not least because the ranch is where her mother is buried.

Sarah’s last visit to Argentina, Martin told us, was in 2011, when she was accompanied by a team from Hello! Magazine.

She was pictured kneeling at the simple wooden cross which marks the final resting place of her mother, who is buried alongside Hector Barrantes, her stepfather and Martin’s uncle.

Martin, who also runs a biotech firm in Buenos Aires and is still involved in the polo circuit, told the Daily Mail that Sarah still part owned El Pucara.

And although some of the surrounding land has more recently been sold off, the plot where Susan and Hector are buried is still part of the estate.

Susan’s decision to split from her husband – who was a polo playing friend of the late Prince Philip and manager of a younger King Charles – caused a huge social scandal in 1973.

At the time, Fergie was just 12 years old and, in an interview more than 25 years ago, she said her mother’s decision to move abroad to Argentina led to her developing an eating disorder.

Fergie later told how she had blamed herself for being abandoned by her mother and turned to binge eating for comfort.

She told The Observer: ‘She [Susan] was my spirit. My whole soul and she went. I believed it was my fault – of course I did.

‘She hardly contacted me at all and that’s when food became my only friend.’

For years, royal watchers noted similarities between the early life of Fergie and the late Princess of Wales, who was also separated from her mother when she was a small child and the two formed a strong bond when they married into the Windsors.

Susan and Hector became a high society couple in Argentina and were well known for their glamorous parties. Each year when the polo season finished in South America they would travel to Europe for the summer.

Susan Barrantes moved to Argentina when she fell in love with a polo player. She died in a car accident aged 61 and is buried on the farm. Fergie is pictured here at her grave in 2011

Fergie’s stepfather Hector died from cancer aged just 51 and is buried at the El Pucara farm alongside his wife, Susan

Widowed Susan continued to live in El Pucara and although some of the land was sold off, it remained in her hands until her tragic death from a horrendous car crash in September 1998

Susan and Hector became a high society couple in Argentina and threw glamorous parties. Each year when the polo season finished they would travel to Europe for the summer

They were primarily there to see Sarah and her sister Jane, but they also took the opportunity to scout out new polo horses.

But the Falklands War in 1982 put an end to their travels for several years, as Argentine players were banned from the UK.

Susan’s connections with the Royal Family had begun as far back as 1954, when she was presented as a debutante to the late Queen Elizabeth, and 22 years later it culminated in her riding in an open carriage with the Duke of Edinburgh for her daughter’s wedding to Andrew.

When Fergie married Andrew in July 1986, the Falklands conflict was still fresh in public memory, and this, coupled with the fact Andrew had fought in the war, meant there was some uncertainty over whether Hector – who himself had enlisted in the Argentine army – would be invited.

But he was – even if he diplomatically elected not to join Susan on the balcony of Buckingham Palace with the wider Royal Family.

Susan returned to Argentina soon after the wedding, but the day had proved to be the beginning of a rapprochement between her and the daughter she had abandoned.

This bond was further strengthened in 1990 when Hector fell gravely ill with cancer of the lymph glands.

Fergie dropped everything and took her then young family, Beatrice, two, and four-months old Eugenie, to Argentina to support her mother, as she spent the final hours with her husband.

Hector, just 51, died just 24 hours after the Yorks flew back to London following a ten-day visit to El Pucara.

At the time the Queen – who had danced with Hector at summer parties during Royal Ascot – sent her condolences.

And Fergie travelled back to Argentina with Andrew, her then husband, for the funeral and burial in the grounds of El Pucara.

Three years ago, in a podcast Sarah – who has herself battled back from breast cancer – spoke of her fight with the disease and recalled how it had previously claimed her stepfather Hector’s life, adding that she had ‘adored him’ and describing him as a ‘wonderful man’.

Widowed Susan continued to live in El Pucara and although some of the land was sold off, it remained in her hands until her tragic death from a horrendous car crash in September 1998 – the same fate that had met Hector’s first wife.

Driving back from friends late one night in a Rover 400 with Martin’s younger brother Raphael, then 25, the car collided at high speed with a Renault truck.

Incredibly, Raphael escaped with minor injuries as did the occupants of the other vehicle. But Susan was killed instantly.

Later reports implied that the crash may have been the fault of Fergie’s mum, amid suggestions that she routinely enjoyed driving at high speed, wasn’t wearing a seat belt and a year earlier had been involved in another potentially deadly smash in which her car had rolled over seven times.

Fergie was on holiday in Italy at the time of the crash, with her Italian friend Count Gaddo della Gherardesca, and immediately flew to Argentina where she met her sister Jane who had arrived from Australia.

Again, the Queen – who was in Malaysia for the Commonwealth Games – sent her condolences and said she was ‘shocked’ and ‘saddened’ by the death – and Fergie was pictured arriving at a small airfield and being embraced by workers from El Pucara.

Despite initial reports Susan’s body would be flown back to England, the funeral took place less than a week later and she was buried next to her second husband on the edge of a polo field – after councillors in Tres Lomas again granted special permission as they had for Hector.

A year before she died, Susan had written a book about her passion for polo called The Sport of Kings, and so in favour was she with the Royal Family that the then Prince of Wales wrote the foreword.

A year before she died, she had also attended the funeral of the late Princess of Wales – which brought her and Fergie even closer together, with Susan increasing the regularity of her trips to the UK and her daughter reciprocating by visiting El Pucara.

They would speak two or three times a week by telephone, with Sarah always keen to know how her mother was doing, and a month before she died Susan had spent the summer in France on holiday with her daughter.

Intriguingly, Sarah’s connections to Argentina and El Pucara also emerge in the Epstein Files – with the first mention in 2007 in an email to the disgraced financier from a woman called Fiona Turney.

Turney, a Briton who now lives in Australia who has connections to the polo scene, had emailed Epstein to ask for work possibilities.

In her CV she described how she had been ‘PA on a project in Argentina for the Duchess of York’.

She added: ‘Initially I was sent to Argentina by DOY [Fergie] to assist in bringing to a conclusion the ongoing legal problems surrounding her deceased mother’s estate.

‘This has recently been resolved, and DOY is now owner of the property. I have produced financial and redevelopment plans for the property, which is situated 600km from Buenos Aries.’

Epstein’s reply is not known, and attempts have been made to contact Turney.

Then in 2010, at the height of Fergie’s financial troubles, her former husband sent an email to Abu Dhabi based financier Terence Allen, in which he asked for help with ‘Sarah’s plight’.

Without naming the creditors, the former Duke of York describes conspiratorially how they ‘have the farm in Argentina and the jewellery as collateral and are not going anywhere with either’.

Mr Allen replies saying: ‘With S – I want to help – sincerely. I am barely acquainted with either of you, so a little lost at what to suggest.

‘Financially I can help. But it seems more meaningful if we find a worthwhile business role within her capabilities.

‘Will you allow me to find something? I don’t want to intrude if you prefer to handle this with the “family” so to speak.’

A year before she died, Susan (pictured) wrote a book about polo called The Sport of Kings, and so in favour was she with the Royal Family that the then Prince of Wales wrote the foreword

But perhaps the most intriguing is an email Epstein wrote to an undisclosed recipient in June 2014 that read: ‘Fergie, helped lent money, mother Argentina rehab.’

It is well known that Epstein bankrolled Fergie with cash and flights – and that she was only too happy to accept, perhaps over-playing her enthusiasm and now bitterly regretting one email describing him as a ‘supreme friend’ urging him to ‘Marry me!’

With all these connections it is no surprise that Fergie, even in hiding, has been keeping in touch with Martin.

Her family in Argentina hope that her current troubles soon recede so that not only is she able to resume some form of public life, but to make more return visits to this place that she loves and also part owns.