I've been spinning in a void since that scorching August day in 1973 when my aunt came and got my sister and me out of the tent in which we were camping in the garden to tell us our mother was dead.

I was nine, my sister was 10 and my brother was 15. My American father had already died of a heart attack four years earlier. Our metamorphosis to orphanhood was complete.

Today, orphans are perceived as a tragic foreign phenomenon. Aid agency appeals for Rwanda use photographs of wide-eyed, bereft-looking children to tug at our heart-strings and highlight the country's plight. Otherwise, the word is an anachronism, charged with Victorian sentimentality, conjuring up visions of bleak institutions and crocodiles of undernourished children.

But the reality is more complex. Our mother spent four years dying. Perhaps more painful than her being dead was the persistent agony of her dying, from cancer of the liver. My recollection of those final months is sharp as a knife's edge; perversely, it is the only time memory has not let me down. Given special dispensations from school, my sister and I visited mother in hospitals and nursing homes. I don't know exactly when it dawned on me that the endless homemade get-well-soon gifts which were received with so much love and grace weren't making her better. I only know that, suddenly, she was cruelly thin and she spoke to me in a whisper.

Mother wrote her will nine months before she died. She judged it appropriate to make our half-brother, not our aunt, our guardian - not a job a 27- year-old bon viveur and journalist, married, with a young son, expected to come his way.

So in November 1973 he placed an advertisement in The Lady: 'Three Recently Orphaned Children need kind, loving, cheerful and intelligent lady . . . to make a home for them. All three bright and very rewarding. Boy (15), shy, articulate, bookish; girls (10 and 9), musical, interested in horses, gardening, sophisticated for age. All at Sussex boarding schools . . .' With a house and a salary as added attractions, the response was enthusiastic.

Looking through the applications today, it's fun to play God and imagine which I would have chosen. Some obviously have eyes on the salary ('Perhaps you could let me know wages,' writes the butler's wife from Scotland). I like the sound of the woman who opened with: 'Have you found someone to love the three children yet? I can't get them out of my mind.' Her husband ran the Human Rights Society, they were photographers, vegetarian . . . Then she blows it. 'We have many interests,' she continues, 'and I have had experience with old ladies, mental patients, cripples, the blind, and prisoners.' Orphan as social outcast, no.

If only we'd been living in the 1840s. As offspring of 'deceased freemen', the Lord Mayor of London would have had custody of us, which would have saved me a lot of speculation. But, as it turned out, we ended up living in Brighton with a spinster found 'on the grapevine' until I was 13, followed by a short bout of unsplendid isolation and, finally, a couple of happy years sharing our new London home with a young Franco-Spanish woman.

Jane Eyre, my most cherished literary orphan, is a typical example of the romanticisation of orphans in art and fiction and the redemptive role they are frequently ascribed. From David Copperfield to Huck Finn, there are plenty to choose from. But it was Jane Eyre's fiery independence and acute sense of isolation that appealed to me as a child - not that I would ever have made my affinity with her public. Like the orphan in Tolstoy's autobiographical novel, Childhood, who resents being called 'orphan' by mourners at his father's funeral, I shied away from the word.

But I've never been able to shake off the reality of my orphaned state. Constantly forced to reveal it by inquiring adults, I soon learnt that a matter-of-fact announcement that my parents 'were dead' caused discomfort. So I honed my responses to make the grown-ups feel at ease. 'My parents aren't alive, but I have lots of brothers and sisters,' I would say. Or, 'My parents aren't alive but I have lots of family in America,' thus fabricating the sense of a close family network and moving the conversation on.

These days, the grown-up asks you where your parents live. They aren't alive, you say. Oh, they reply. And that's it. You never get a decent response. You never get the chance to protest about how angry and cheated and alone you feel, how you're completely sick of being different. It's then that Joe Orton whispers in your ear, tempting you to add that your father collapsed while celebrating the anniversary of the Battle of Mons and your mother was buried with glass eyes. At least you might get a reaction.

Death makes people pompous, too. An orphan's existence is shrouded in melodrama. Everybody but everybody assumes that your parents were killed instantaneously in a horrible car crash. Because this notion of orphan as crisis victim offers a means of comprehending such an unnatural, inconceivable state.

Orphans throw a spanner in the works. We certainly did. If the family is the building block of society, orphans are the rubble in the pile. A family is hermetically sealed; orphans are rebellious, roaming, exiled. An orphan is a firecracker in its midst, forcing doors to open that would rather stay shut, forcing down barriers of class and family identity. That's why orphanages and workhouses were so appropriate: big buildings to contain these anarchic forces. But there was nowhere to put us. We were 'private' orphans, with our own funds. My impression of my childhood is of being shunted inexplicably from one set of faces to the next as one person after the next dropped the ball.

One day, soon after my mother's death, I eagerly waited for my mother's partner, Richard, to pick us up for an outing. I was wearing my best dress. But he never showed up and I never heard from him again.

The mechanics of adult self-interest, so unfathomable to children, were already set in motion. From then on, I started to learn the chameleon's art: the necessity of adapting to different social groups, both in a desperate bid not to stand out and, like Kipling's Kim, in a quest for identity and a sense of belonging.

I never wanted to look or feel like an orphan and I didn't want my brother and sister to do so either. This anxiety drove a splinter through the triumvirate; we were each out there on our own, observing each other's battles silently, embarrassed and sad when one of us floundered or handled the inevitable question awkwardly, yet quite unable to verse each other in survival tactics for what had become a very adult and alien world.

There was an unspoken rule to be nice to everybody in case word went round that the Foxes were playing up. Like all orphans, we held registered charity status. As dependants, we were not in a position to be contrary or ungrateful. We felt we were irksome, inconvenient, that we were causing other people trouble, people who would prefer to get on with their own lives without the albatross of three transatlantic children around their necks.

If orphans 'come through the fire', as the bereavement psychiatrist Colin Parkes puts it, they are often 'tougher and more self-contained adults'. 'But,' he adds, 'there is a well of loneliness which is easily tapped into, even in adult life.' Jane Eyre and I would drink to that.

But at least orphans don't suffer what psychotherapists term 'reality conflicts'. Our image of our parents may be false, but we're none the wiser, too busy fantasising about them being alive. Even just for a week. And you'd forgive them anything. Pitching up late for school. Wearing unfashionable clothes. Anything.

Because of the memory haze, the distortion and displacement of facts is humiliating. Discovering only this week that you were nine when your mother died, not eight, as you've been telling people all your life. Visiting your father's grave for the first time, aged 22, and realising you have no image of him that is entirely your own because your already slippery memories are contaminated by dreams and hearsay.

Scrambling for the pieces to a constantly changing, bumper-edition jigsaw puzzle trips you into the same snare of illusion that the anthropologist Levi- Strauss bemoans in Tristes Tropiques. An 'archaeologist of space', he seeks, in vain, to recreate the details of ancient tribes through bits of old stone and debris while travelling in the modern world.

(Photographs omitted)