Image copyright Alamy Image caption "Nobody knows exactly what the sexual charge was between Adolf Hitler and Unity Mitford," her biographer David Pryce-Jones says

As one of the high-society sisters who enthralled and scandalised 20th Century England, Unity Mitford's return home from Germany in January 1940 caused an outcry. Fresh from an ill-fated dalliance with Adolf Hitler and with a bullet lodged in her brain, Unity had the government, MI5 and the nation's gossip columnists hot on her heels. So how did she end up living with a family in a quiet Warwickshire vicarage?

The first memory Margaret Laidlaw has of Unity Mitford is of her standing under a chestnut tree in Leamington Spa with Margaret's mother.

Margaret, who was eight years old, remembers the most notorious of the Mitford sisters looked like nobody she had ever seen before.

"She was very tall with a lovely ruby brooch at her neck - she always wore that. She had fair hair. That's my first real memory of her," Margaret said.

"My mother said, 'This is Auntie Unity and she may be coming to stay with us'. I remember feeling confused - I had never heard any mention of an Auntie Unity.'"

Image copyright Margaret Laidlaw Image caption Unity was installed in the vicarage as a permanent house guest, living there with Margaret and her sister

A few weeks after that first introduction, Unity was installed as a permanent house guest at the vicarage in Hillmorton, Warwickshire, where Margaret lived with her father the Rev Frederick Sewell-Corby, her mother Bettyne and her younger sister.

Margaret remembers watching bewildered as her father's clothes and books were removed from her parents' bedroom.

Margaret's mother had to sleep in the same room as Unity and nurse her through the night.

"Unity was incontinent - I knew this from the sheets galore that were hung out on the line each morning," Margaret said. "And she had a leg that was paralysed and swung like a log when she walked."

Margaret's father went to sleep in his dressing room and locks and bars went on all the vicarage doors and windows.

Image copyright Fred Ramage Image caption Unity was returned to Britain via Switzerland after her suicide attempt in Germany

"I think Unity was under what you and I would call house arrest," Margaret said. "She was never, ever alone."

But unbeknown to the little girl, "Auntie Unity" was no relative and her reputation was notorious.

She had been discussed in the House of Commons. Her whereabouts was considered to be a matter of national security.

For she was rumoured to be the girlfriend of Adolf Hitler himself.

Image copyright Hulton Archive Image caption Unity's sister Diana married Sir Oswald Mosley, leader of the British Union of Fascists

The sister with the swastika

Unity was one of the six Mitford sisters who were the daughters of Lord Redesdale

Her sister Diana married Sir Oswald Mosley, leader of the British Union of Fascists

"Unity saw her beautiful older sister making waves and wanted to go one better, by picking up Hitler," says Unity's biographer David Pryce-Jones

She discovered where Hitler liked to have lunch with his cronies in Munich and waited there until he asked her to his table. She wrote she considered the Fuhrer "sweet"

Hitler invited Unity to his box at the Berlin Olympics and paid for a flat in Munich for her

Most historians do not believe there was a sexual relationship but Mr Pryce-Jones estimates she met Hitler about 100 times. "Nobody English got so close to Hitler," he said. "She was right in the inner circle of the Nazi leadership"

Media playback is unsupported on your device Media caption Footage shows Unity Mitford joining Hitler at his mountain retreat

She had returned to England, after several years in Nazi Germany, following a failed suicide attempt.

When Britain declared war on Germany in September 1939, a distraught Unity went to the Englischer Garten park in Munich (the English Garden) and shot herself in the head.

Upon her return to Britain - with a bullet remaining lodged in her brain - she was vilified as an enemy of the state and the Home Office faced calls to have her interned.

Image copyright Alamy Stock Photo Image caption Unity "was right in the inner circle of the Nazi leadership", according to her biographer David Pryce-Jones

It was finally decided the vicarage in Hillmorton was a safe enough haven for Unity - a place where she could receive the care she needed and live a less troublesome existence.

Lady Redesdale, Unity's mother, was a client of Margaret's mother, a chiropodist, and it was agreed Mrs Sewell-Corby could act as Unity's nurse.

"The vicarage was always open to everyone," Margaret said. "People that were down-and-outs came and asked us for a cup of coffee.

"My mother obviously thought it would be kind to have her. No doubt there was a lot of government correspondence going on.

"I think [my father] found it very, very difficult. He was doing his wartime effort, which was to look after a potentially dangerous person.

"Unity had no money, she had no passport, she had no writing paper. She was allowed absolutely nothing at all. For a while, she wasn't even allowed a library ticket."

Image copyright Alamy Image caption Unbeknown to the young Margaret Laidlaw, her family's new house guest had a notorious reputation

Margaret believes Unity stayed with the family for long periods between 1943 and 1948. The arrangement was largely kept secret.

"We weren't allowed to talk about it to anyone," she said. "It was just completely taboo.

"No doubt my parents were extremely worried and concerned but I had no idea at all about it. I didn't realise she was under lock and key. She was just a visitor."

Some historians have suggested Unity was carrying Hitler's love child - although Margaret insists there is no evidence of this.

"It's absolute rubbish," she said. "I don't believe she was capable of having any children."

Fondness for fish and chips

Image copyright Getty Images

According to MI5, Unity was "mentally unsound" and "harmless"

However, the Home Office reported complaints from members of the public that Unity was "driving about... picking up airmen". The local police inspector was forced to launch an investigation

Mrs Laidlaw says Unity's presence in the vicarage was probably not popular with locals. "I'm not sure people were happy to have someone so closely connected with the enemy in their midst," she said

But she was, nonetheless, a source of fascination. John Howes, from Rugby, remembers his grandfather Frank telling him about Unity's fondness for chip suppers. "She used to go walking through Hillmorton eating fish and chips. My grandfather was amused by this sight as she was 'a member of the aristocracy'," Mr Howes said

Unity brought with her a dog Lieblich, a dachshund said to have been given to her by Hitler.

The Mitford sister had to be accompanied everywhere. Despite the atmosphere of constant surveillance, Margaret remembers these periods as happy times.

Image copyright Margaret Laidlaw Image caption Unity brought her dog, Lieblich, to the vicarage - he was said to be a present from Hitler

"She was always very cheerful, very jolly," Margaret said. "She was a very good artist. We used to pick ragged robin and dog roses on the country lanes and we would come back and she would show us how to paint them.

"I don't remember being in the room with her for any length of time on our own. Mother was always there, knitting or playing the piano.

"My memory is that Unity liked Bavarian marching songs and would stride around singing. I remember she had a record player and a lot of 78 records. She was a very good singer - a bit loud and very spontaneous."

Media playback is unsupported on your device Media caption The Warwickshire stay of Hitler's British 'girlfriend'

Margaret now believes she and her sister were protected by their mother and father from some of Unity's more extreme views.

"I'm sure our parents were very careful," she said. "There was great emphasis on the fact that the Jews were as good as anybody else.

"In later life, I was horrified to discover Unity was anti-Semitic. I think my parents did a very good job in keeping that one away from us."

Image copyright Hulton Archive Image caption Unity tried to kick Margaret when she failed to express regret over the death of Hitler

Margaret clearly remembers the final days of the war in Europe, as word of Hitler's suicide in a bunker in Berlin reached the breakfast tables of Britain.

"My sister said, 'Morning Auntie Unity. I'm so sorry your boyfriend's died' and she said, 'Oh, you are such a sweet child'," Margaret recalls.

"And I said, 'Oh - that man'. And she went for me - she went to kick me and I fled under the dining room table to get out of her reach."

Image copyright Margaret Laidlaw Image caption Margaret believes her father - pictured here with his family - was doing his bit for the war in looking after Unity

Later that year Margaret was sent to boarding school. She believes Unity continued to live with the family during term-times but in the holidays travelled to the Scottish island of Inch Kenneth, where she lived with Lady Redesdale.

"Latterly Mother went up there to nurse her because Lady Redesdale knew she could trust my mother implicitly not to say anything to anybody," Margaret said.

Image copyright Margaret Laidlaw Image caption Today Margaret, 82, lives in Dunbar and is an MBE for her service to the children's charity Unicef

Unity died in 1948 in Oban at the age of 33 as a result of meningitis caused by swelling around the bullet lodged in her brain.

"We came home from school and Mother was upstairs in the bathroom crying," Margaret remembered.

"I looked at Daddy and he said, 'Thank God it's all over.'"