The NS Profile - The Duncan Smiths

They include a Spitfire pilot linked to a Nazi spy ring, a Europop queen, a fashion king and a balle

Madame Tussaud's has judged Iain Duncan Smith to be the first Tory leader too boring to merit a wax replica. So how anaesthetisingly dull must his family be? Well, his immediate relatives include a chart-topping singer, the former head of Prada UK, a leading exponent of gun legalisation in Britain and a Second World War hero. Could IDS be interesting after all?

Despite attacking Blair's "exploitation" of his children, IDS has brought his own family clearly into the public spotlight. During the leadership race, he allowed his supporters to echo Norman Tebbit's comment that he was a "good family man" as a contrast to the troubled Michael Portillo. Speaking last November to the Assembly for Evangelical Christian Leaders in Cardiff, he voluntarily gave some insight into his home life with four children.

"I think having the family helps tremendously because the greatest level [he meant 'leveller'] of all are your children." He added that his kids "turn around basically and say you are useless most of the time which brings you back down to earth".

He has been even more keen to draw his father and siblings into the public domain. He explains his decision to enter public life as a result of growing up in a home where, "because of my father, the ethos was service". Group Captain Wilfred Duncan Smith was one of the most successful Spitfire pilots of the Second World War, shooting down 19 German aircraft and receiving the Distinguished Flying Cross.

IDS has boasted about his father's success, and it might have played a role in his winning the Tory leadership. He was eager to place a large article in the Telegraph during the campaign about his father's war record - a factor that would certainly have played well with the Conservative Party's elderly membership. The pressure placed on IDS by his father emerged when he explained: "I grew up believing and having drummed into me all the time the sense of something bigger than yourself, giving to something bigger - your country."

Wilfred was, however, a rather more secretive and puzzling figure than his son would like us to know. It has recently been disclosed that he was interrogated in 1940 in connection with a Nazi spy ring. Wilfred had fallen into the company of figures with far-right sympathies, in particular members of the Right Club, a sect which believed that Hitler would win the war. (Half a century later, IDS found himself mixing with far-right groups such as the Swinton Circle and the Alleanza Nazionale.) As part of these investigations, Wilfred was questioned - and revealed the existence of a mysterious first wife. They had separated after a year, but IDS's father kept her so secret that the Duncan Smith family claims even today not to know her name.

Wilfred's 1981 memoir of his war experiences, Spitfire into Battle, has a familiar ring to anybody who follows IDS's speeches. Both have a buttoned-up, dry prose style, peppered by very occasional (and clearly long-repressed) moments of bitter cruelty. Wilfred harboured a particular dislike of the "Huns", but this did not apply only to Nazis. As a student travelling on the Continent, he found the German people "arrogant . . . noisy and not a little rude . . . They laughed in an offensive way, [and] they bored me." Later, he says approvingly of one pilot, "He hated all Germans."

Wilfred's contempt for politicians is also starkly expressed. He calls them "posturing" and boasts that he has "no interest" in them. This view is shared by IDS's Irish mother, Pamela, who said recently that she did not expect her youngest son to go into politics. He was, she explained, "too silly" for the job. She also revealed some of the family's internal dynamics: "He [IDS] used to say it was murderous having two sisters . . . The sisters always bullied their three brothers, you see."

Pamela was a ballet dancer until she met and married Wilfred in Rome in 1946. It was her career that prompted Petronella Wyatt to ask IDS what must surely be one of the most idiotic questions in the history of political journalism: "How does your mother's experience of ballet help you in the dance of politics?"

Oddly, despite the family ethos of public service described by IDS, the Tory leader is the only one of Wilfred and Pamela's five children to take up this mantle. The eldest of their sons, David, has risen to the top of the fashion industry, having headed the UK operations at both Louis Vuitton and Prada, thus raising the surreal possibility of IDS rubbing shoulders with Absolutely Fabulous-style fashionistas at Bolly-fuelled parties.

David's performance at Prada has been questioned. As Annalisa Barbieri, the New Statesman's fashion correspondent, explains: "In my opinion, Prada is on the brink . . . Its designs are still much sought after and lauded, but they've invested heavily in the past few years [on David's watch], often seemingly unwisely, and done things which I don't think have helped their image. So fashion-wise, good; corporate image, arrogant." Both brothers, it seems, have had to confront the challenge of leading big, unwieldy organisations with a reputation for arrogance. Worryingly for the Tories, David didn't succeed in transforming that image at Prada. If anything, he further cemented it.

David quit Prada to become the chief executive of the Luxury Brands Group last September. The company, formed from the marketing services firm Cardington, had little experience in fashion prior to acquiring the prestigious couture houses Hardy Amies and Hartnell, both dressmakers to the Queen, last year. It gives us some hint about the Duncan Smith family's politics that David has chosen to be associated with a name synonymous with snobbery. Sir Hardy Amies himself, now in his nineties, shamelessly built his brand around social hierarchy, once claiming that even God should wear a five-button suit.

Snobbery seems to be a recurring theme in descriptions of the family. Even sympathetic interviews with IDS in the Telegraph have noted that "there is a whiff of snobbery about him", that he considers himself to have "married up" (his wife is the daughter of a hereditary peer) and that he has a "gentlemanly condescension to the ladies".

David is now imitating his former employer LVMH (Moet Hennessy Louis Vuitton) by buying up several brand names and trying to build them into a bigger business. His task is similar to his younger brother's. As Kim Winser, who has been hired to revitalise the Pringle fashion label, explains: "A lot of British brands have relied too heavily on their heritage but have not remade themselves for the future." Iain, who is trying desperately to move away from the familiar and toxic Thatcher brand, will have plenty to discuss with David at family reunions, then.

One of IDS's sisters, Susan Duncan, has adopted a similarly unusual career path.

She was a Europop queen in the 1970s. Her music - which can still be found on various Napster imitators on the web - is dire sub-Eurovision gibberish, with lyrics such as, "Side by side we soar/me and you just glide/we are gaming in a fall a fall a fall/we fall." The mystery of Continental taste in music continues with the revelation that as one half of the band Susi and Guy, she made it to number three in the French charts.

The family has clearly been briefed not to give comments to the press.

Susan, who now has a senior position with Sony Music in Rome, pronounces in a cut-glass accent: "I have less than no interest in speaking to journalists. My singing career was a very long time ago, and my brother can speak for himself. You are wasting your time and mine. Goodbye."

With such eclectic blood relatives, IDS might have been expected to marry into a rather more sedate family. But, on the contrary, IDS's father-in-law, the 4th Baron Cottesloe, was also a rather unconventional figure. He was one of Britain's leading defenders of privately owned guns and firearms. IDS is more than comfortable mingling with the pro-gun lobby. He has an extensive web of contacts in the pro-gun US Republican far right, where he was a regular on the lecture circuit before becoming Tory leader. The late Baron Cottesloe used his inherited position to champion these policies, opposing the legislation to ban handguns following the Dunblane murders. He said that the bill achieved nothing "other than stress and agony".

IDS has self-consciously adopted the habits of the upper-class family he married into. He spends a great deal of time in the countryside, where he shoots and ferrets, and his eldest son is educated at Eton.

He is the first leader of a major political party since Alec Douglas-Home to be linked by family and temperament to this kind of old right, huntin' and shootin' aristocracy. It is a remarkable regression for a party once so proud of being led by a grocer's daughter and by a boy from Brixton.