Sarah Harrison (centre) speaks to the media outside the Ecuadorian embassy in central London in 2012.

London - They are the kind of quietly decent, middle-class people universally recognised as the backbone of England.

Now retired, Ian Harrison used to be an executive with clothes retailer Burtons, while his wife Jennifer has devoted her life to developing methods of helping children with learning difficulties to read.

Not the kind of family to be involved with the story of an international spy fleeing from justice - unless they were watching a blockbuster film. But all this week at their cosy farmhouse in East Sussex, they have thought of little else.

For their beautiful, privately schooled daughter Sarah, 31, is the “mystery” long-haired girl who has been shepherding former CIA technician Edward Snowden in the glare of the world’s media as he makes a diplomatic dash to escape the wrath of the White House.

Sarah, who has been the lover of charismatic WikiLeaks leader Julian Assange, 41, and has become a pivotal figure in his organisation, has been holed up most of this week with whistleblower Snowden in a hotel in the transit area of Moscow’s Sheremetyevo airport.

Russia says that, since Snowden has not passed through immigration, he has not technically entered the country. President Putin has refused him entry and declared him “free to go” wherever he wishes, “the sooner the better”.

His planned destination is Ecuador, to which he has applied for asylum, even though the US has revoked his passport.

Ecuador has given asylum as well as board and lodging to the supercilious Assange in its London embassy, where he is under siege after more than a year as he tries to avoid being despatched to Sweden to answer sex charges.

Snowden, meanwhile, has been charged with espionage by the US after his exposure in The Guardian of Prism, a covert security project run by US intelligence that pries into Facebook accounts, emails and phone calls.

He also revealed details of major electronic eavesdropping by Britain’s GCHQ called Operation Tempora, describing it as “the largest programme of suspicionless surveillance in human history”.

The former analyst was in Hong Kong when the US laid the spying charges that could put him in jail for the rest of his life, and America immediately sought extradition.

But the authorities there refused to send him home because of a misspelt name on the extradition application form. (Snowden also claimed the US hacked into millions of Chinese mobile phone messages, which hardly made the Chinese state sympathetic to Washington’s request.).

Enter Sarah, who has become an expert on immigration and extradition matters through the plight of Assange, whose visitors at the Ecuadorian embassy, where he has a desk and a bed, are vetted by her.

She is also said to do Assange’s washing at her London flat, and even though WikiLeaks had nothing to do with the latest whistleblowing revelations, Assange instructed her to fly to Snowden’s side in Hong Kong and help him in his request for asylum in Ecuador.

One prominent supporter says: “WikiLeaks can’t afford not to be involved in such a major leak issue.”

So Snowden’s future freedom is largely in the hands of Sarah, whose friends describe as “very committed, very determined and a good organiser who loves being at the centre of things where there is some excitement”.

“She knows what she’s doing - she’ll be fine,” one says.

Unsurprisingly, that’s not how Ian Harrison and his 60-year-old wife see it. They never expected to find their daughter at the eye of an international diplomatic storm.

“We haven’t heard a thing from Sarah and I’m worried - though not nearly as worried as my wife,” admits Mr Harrison, 74. “All I know is what I read in the newspapers. Sarah’s always been very conscientious, diligent, and I believe she’d like to see the world a better place. But heaven knows where this could end.”

It’s certainly not what they had in mind when they sent Sarah to Sevenoaks School (boarding fees currently £29 600 a year).

Former pupils include Princess Anne’s husband, Vice Admiral Sir Timothy Laurence, the triple-Oscar-winning actor Daniel Day-Lewis, as well as - and how juicily ironic - Sir Jonathan Evans, head of MI5 for six years until this April.

Sarah was a good runner and swimmer and bright, too - “a good all-rounder who enjoyed her time at the school”, says her father proudly.

From there, after doing well in the international baccalaureate and taking a skiing-and-travelling gap year, she read English at Queen Mary, University of London, and later, after more travel, decided she wanted to be a journalist.

None of this can be found in standard internet searches or is included in a “biography” of her put out by WikiLeaks. Like other figures in the organisation, she appears to have wiped her online profile off the net for privacy purposes - hardly what one expects from those dedicated to the exposure of information and the public’s right to know.

These, after all, are the people who see themselves as the global defenders of free speech, valuing it so highly that they ignore fears that their disclosures threaten the national security of democratic nations and possibly even world peace. One American Congressman described them as “terrorists”.

How different is their attitude to their own secrets and security - damningly illustrated by Assange cowering in an embassy instead of doing what most men protesting their innocence would surely do, flying to Sweden to clear his name.

Sarah’s deep commitment to WikiLeaks is seen, in part at least, as being driven by her fascination with Assange. “All the girls are hypnotised by him to one extent or another,” says one senior supporter.

It started in 2009 when, having reached the age of 27 without becoming a journalist, she successfully applied to be an unpaid intern researcher for the charity-based Centre Of Investigative Journalism, which trains and helps journalists and is based at City University, London.

She was positive, bright, enthusiastic, and, in 2010 was taken on as a junior researcher by the newly established Bureau Of Investigative Journalism, a professional operation also housed at the university - and whose reputation is now badly damaged since its misleading television report that led, wrongly, to Tory peer Lord McAlpine being identified as a paedophile.

Sarah was involved in helping sort files for television documentaries on the Iraq war passed to them by Assange. He was newly arrived in London and spent days at the bureau office strutting around in jeans and a stab vest and, says one of Sarah’s friends, “trying to get all the women salivating”.

Later that year, Sarah’s affair with Assange began. She stayed with him at his room at the Frontline Club in Paddington until he was arrested and held on remand in Wandsworth jail pending extradition proceedings over assault allegations involving two Swedish women.

When he was granted bail and went to stay in the Suffolk manor house of former Guards officer and WikiLeaks supporter Vaughan Smith, Sarah went with him.

And when he stayed at the home of another supporter, Tunbridge Wells businesswoman Sarah Saunders, Sarah was there, too.

With these supporters, as well as Jemima Khan, film director Ken Loach and others, Sarah helped to cover Assange’s bail. It was £5 000 in her case, of which she lost £3 500 when he went into the protective arms of the Ecuadorian embassy in Knightsbridge more than a year ago.

WikiLeaks workers are known to be paid very little. So where did she find the money - from her father?

“Oh, I can’t say,” says Mr Harrison, who is charming but discreet.

His educational consultant wife worked for Kent County Council until her department was closed two years ago. She now runs a company offering reading programmes for children with learning difficulties.

Friends of Sarah say she took Assange to meet her parents at their farmhouse before he fled into his embassy refuge, but Ian Harrison declines to confirm or deny it - “I can’t comment,” he says. But he does refer to Assange as “Julian”.

As for WikiLeaks, he will only say: “My daughter is a great girl who has her own life these days.”

She and Snowden are seemingly stuck in limbo in the airport in Moscow, as Ecuador has now warned that it could take “months” to process his asylum application.

Some, of course, refer to Sarah as being Assange’s “ex” girlfriend, but others believe this is only because he is incarcerated in Knightsbridge.

“She was very enamoured of him, and he of her striking looks and positive thinking,” says one close figure. “She really is a terrific girl with a great sense of fun, and she’s clever. It’s hardly surprising that he’s behind her growing power in the organisation. They’re closer than ever.”

So, how would Ian and Jennifer Harrison view the idea - just the idea - of Julian Assange becoming their son-in-law? “Well,” says the former Burtons man, “strange things do happen in this world.” - Daily Mail