She's the relative who addressed you as an adult when all others treated you as a child, the wearer of hats that nobody else would be seen dead in, and the valued confidante who shared your teenage agonies. Long live the aunt, writes Rupert Christiansen
Let's hear it for the aunts. We're taught to honour our fathers and mothers, siblings are extensions or reflections of ourselves, and grandparents also get their due. But whoever stops to think about, let alone thank, those women on the sidelines of the family, whose friendship and affection can play such a richly nurturing part in the lives of the young?
The dotty aunt who smoked cigars, the sad spinster aunt with a tremor and hairy moles, the opera-loving aunt who wore embarrassing hats, the aunt who took you to see The Sound of Music, the aunt who went to live in California, even the auntie who wasn't blood-related at all but just a longstanding family friend who lived in the next street - all these are part of the great unsung romance of aunthood.
It's a story that only stretches back some 250 years. Auntly relationships don't exist in the animal world. There are no aunts of any significance in the Bible. The only aunt that engaged the interest of ancient Rome was Domitia Lepida, who brought up her nephew Nero, only to be murdered by him when he became emperor. We never get to meet Lysander's aunt, who is mentioned in the first scene of A Midsummer Night's Dream as providing a possible refuge for the fugitive lovers, and Shakespeare never dramatises aunts elsewhere.
But suddenly, in mid-18th-century Europe, aunts come to prominence - not only in letters and memoirs, but also in novels, many of which contain the character of an aunt in whom the heroine confides. Quite why this should be has puzzled scholars, and some have suggested that the phenomenon can be ascribed to changes in the marriage laws and increases in mobility which gave young women more independence from their mothers, thus leaving them in need of a mature female capable of offering impartial advice (hence the agony aunt). If this sounds fanciful, just think of Elizabeth Bennet in Jane Austen's Pride and Prejudice, and the difference between her ghastly infantilising mother and the calm, mature Aunt Gardiner, who talks to her as though she was an adult and takes her away on holiday.
We should also remember that at a time when so many mothers died young or in childbirth, aunts were often called upon to assume a mothering role. One such was Aunt Branwell, a straitlaced lady from Cornwall summoned by the depressive Rev Patrick Brontë to the wilds of the Yorkshire moors to take charge of six motherless infants after his wife Maria died. Aunt Branwell was reluctant to accept the responsibility, but had little option in the matter and spent the rest of her dreary life in Haworth Parsonage. She established "order, method, neatness in everything", as well as instructing her nieces in religion and sewing. But it was only her namesake nephew, Branwell, who touched her heart.
A century later, Mimi Stanley made an even greater commitment. When her sister Julia was deserted by her feckless husband Alf Lennon, she took sole charge of their five-year-old son John, giving him a middle-class childhood in a leafy suburb of Liverpool - their semi-detached home is now owned by the National Trust. Mimi and John were strong characters, and throughout his adolescence they fought, sometimes bitterly. "I never forgave my auntie for not treating me like a genius," he said after The Beatles had become famous. But deep down he adored Mimi, who never failed to tell him the truth about himself. Nothing fazed her: when he and Yoko Ono appeared nude on the cover of the Two Virgins album, she merely said: "It would have been all right, John, but you're both so ugly."
The annals of aunthood are rich in eccentrics - some nice, some nasty, but all fearlessly themselves, untrammelled by convention or decorum. In fiction, perhaps the most celebrated are the good Aunt Dahlia and bad Aunt Agatha of PG Wodehouse's Bertie Wooster; in drama, there's the monstrously cynical Lady Bracknell in Oscar Wilde's The Importance of Being Earnest. But such larger-than-life aunts did exist in reality. The aunt in Patrick Dennis's autobiographical novel Auntie Mame, on which both a film and a musical were subsequently based, was actually called Marion and (in 1929) did talk outrageously to her 10-year-old nephew about lesbians and the Oedipus complex.
No wonder aunts cut such potent figures in children's literature. Classic American tales of orphans such as Tom Sawyer, Pollyanna, What Katy Did and The Wizard of Oz show them as starchy, but generally admirable; more recently, they seem to be painted in darker colours - Aunts Sponge and Spiker in Roald Dahl's James and the Giant Peach, for example, or Harry Potter's Aunt Petunia, not to mention the dreary Selma and Patty, whose visitations to sister Marge Simpson cause her son Bart such anguish.
Aunts aren't a worldwide phenomenon: some languages and cultures, particularly in sub-Saharan Africa, don't seem to recognise their existence at all, while others specify separate words and roles for maternal and paternal aunts (in Japanese, rather alarmingly, the word for mother's sister, amitam, is the same as that for father's concubine).
Aunts have a particularly vivid life in the US, where they are widely used as a marketing catchword, reassuringly evoking the old-fashioned or home-made, and attached to everything from "cozey" bed-and-breakfast establishments to rich desserts or fancy quilts. A mythical figure as vivid in the popular imagination as Betty Crocker or Ronald McDonald is Aunt Jemima, whose pancake and waffle mix ranks as one of the nation's oldest manufactured foods. The picture on the packet used to depict a smiling black mammy wearing a bandanna; now, in deference to changed sensibilities about stereotypes, she looks more like Oprah Winfrey.
Yet there's a sense that the aunt is finally in decline. Her work is done. Young women no longer want to be called aunt anything - it's ageing and unsexy, and children no longer find the idea of an aunt exotically engaging. This seems to me to be a great pity.
My own late Aunt Janet, who had no children of her own, was a wonderfully liberating influence on my childhood. Of course, she didn't have the hard daily graft of child-rearing that was my mother's lot, but my annual visits to her musty Victorian house in Norfolk were always occasions of imaginative enrichment. She told me about books she had read and music she had listened to - and she had a knack of stimulating my interest so that I wanted to try these for myself. So thank you, Aunt Janet, for the lifelong gifts of Jane Austen and Benjamin Britten.
But she wasn't just a cultural guide, or a surrogate teacher. When I was in those crucial pubescent years from 10 to 14, when boyhood begins to fade, she treated me in a slightly more adult way than anyone else did. She didn't feel impelled to discipline or judge me, and she wanted to hear what I had to say. In doing that, she opened up to me a new way of relating to adults, based on friendship rather than authority - and that, I think, is the supreme gift that a relationship with an aunt can offer.
• The Complete Book of Aunts, by Rupert Christiansen, is published by Faber & Faber (£12.99 in UK)