Kate Mosse: The great stocking swindle

Memories shift, crack, slide over time. Some become more colourful, distinctive, significant. Others retain the power to sting, to undermine, to wound, even decades after. We ascribe adult motivations to childish impulses, paint ourselves in a more flattering light. We read novels, about childhood, of coming age, and are seduced into thinking of ourselves as more thoughtful, more original than ever we were.

Of all of the myths, that of Christmas holds us most tightly. Ghosts of winters past, present, yet to come, snag our attention. Chestnuts roasting, sleigh bells, all things not commonly, in truth, found in Sussex in the 1970s. But it is often, aside from the platitudes and clichés, a season of transformation in ways unexpected.

My before-and-after Christmas was in 1970. I was nine, my sisters, five and four. I was aware – I must have been, even though I didn't quite yet wish to acknowledge it, that Father Christmas was a wonderful fairytale. In public, he took up residence during December in the grotto on the first floor of the Army & Navy Stores in Chichester. In private, on Christmas Eve, I knew there was a different sort of illusion; that my mother chose, bought and wrapped the stocking presents and then, at some moment after the grandmother clock in the hall had chimed the lateness of the hour, my father tiptoed into our bedrooms on Christmas Eve and filled up the three old, woollen stockings with gifts.

And yet... I was not quite ready to let go of the illusion. Looking back, as a parent and in middle age, maybe it was deliberate, this testing of the waters? Maybe not. But, on 24 December 1970, I got myself proof positive – and was inadvertently responsible for the worst family Christmas ever.

My mother's strategy for stocking presents was simple and lovingly delivered: different, but equal. We each had a version of the same thing – pencils, sweets, socks, a new torch, stationery, this little book or that, hair slides and clothes for Sindy or Barbie – gifts appropriate to our interests and our ages; nothing too much. Proper presents came later, under the tree.

I cared only about one type of present. My October birthday had delivered to me quite the most beautiful dolls' house. It was not as grand as those I'd seen in the old toy museum in Arundel or nearby West Dean house, with several floors and central staircase and figures in period costume, mob-capped servants and whiskered men, the whole life of an Edwardian family, upstairs and down. Mine was a modern house, more modest. But it had a clever contraption at the back, where a battery could be set to fire up the lights in every room. And it had a hinged front. But I didn't have much furniture, not nearly enough, and it was two weeks of saving pocket money to buy even the plainest of beds or dining-room chairs. What I wanted most of all was the proper old-fashioned stove for the kitchen, for which I'd been saving up for five weeks already.

I'd like to think now, through the filter of 37 Decembers, that it was anxiety that was father to the deed. Given the demands upon his time, how could Father Christmas possibly know how important it was that I was given certain furnishings and fixtures rather than others? That that's what I wanted at all? Even assuming he was fair and even-handed – and my sisters were also given one piece of furniture too – they might not be prepared to swap. This was the era of Swap Shop. My middle sister, Caroline, was mad keen on Scalextric and cars and didn't really care much about her dolls' house at all. A chest of drawers, an ironing board; it wouldn't matter to her. My little sister, Beth, was already passionate about animals, particularly horses; would put whatever piece of dolls' house furniture she got into the middle of her model farm that was filling most of the playroom floor. But maybe they wouldn't want anything I had to offer?

My sisters and I always opened our stockings together on Christmas morning sitting on our parents' bed. It spoiled things to do it alone and to cheat, fumbling with Sellotape and crepe paper in the dark of one's own bedroom. But this time it was imperative I knew what lay in store. If I was to be disappointed, and not get the stove with its perfectly symmetrical cooking rings, polished rail, double doors, I wanted to have time to be disappointed in private. Forewarned. And, what if my sisters had things I wanted? A waste, surely.

I kept vigil, counting the minutes down. But, lulled by the familiar sounds of the central heating clicking off, the sighs and breaths of the house, the thumping of hot-water pipes in the airing cupboard, I fell asleep. When I woke again, all was silent and the stocking was misshapen and full.

I cannot be sure, now, if I intended to swap the presents all along, but in an old winceyette dressing-gown and bare feet, I left my room with my stocking and took those from my sister's rooms, then carried them to a corner where the light was less likely to be seen by my parents, should they have awoken. In front of the old wooden book case with the sliding glass doors filled with books from Readers' Digest, I unpacked each into three separate piles.

As I'd expected, there were absolutely equal numbers of presents, although each had different colour of wrapping paper. I do this still for my own children, even though they are teenagers. This presented a dilemma. If I wished to swap the dolls' house furniture – and absolutely I did – then I was going to have wrap things up again in the relevant sheet of blue, green or white stretchy crepe paper. They might not quite fit the original shape or size. I'd like to think I paused. We had two pieces each. I slipped from wishing only to know what was to come, to the idea that it would be all right to redistribute the presents all together, equally and fairly. Since I had thoroughly persuaded myself that my younger sisters would prefer sparkling socks, white and red Lego blocks, anything, in fact, other than dolls' house furniture, I could keep all six pieces for myself.

How long did this raid on the spirit of Christmas last? I have little sense of time passing now, even less when I was nine. I ended up with three rearranged stockings, coloured coded still, a rearrangements to suit us all.

I always loved – and do still love – Christmas. The morning of 25 December 1970, though, is too sharp, the texture of the memory too rough at the edges. My sisters, generous and excited and not expecting such treachery, didn't notice the slightly shoddy wrapping, the corners of Sellotape unstuck. But my mother did. As one by I revealed the dolls' house pieces, her face seemed to harden slightly. Confusion, surprise, realisation. I understood, then; no possibility of misinterpretation or excuse. She knew precisely what present had been put in which stocking. Without a word, my mother left the torn paper and squeals and arguments over whether eating a whole chocolate orange before lunch would spoil our appetites, and went to see to the turkey. Her dilemma, with hindsight, is obvious. She did not wish to spoil things for my little sisters, but she knew what I had done.

I cannot remember, now, when the guilt became too much and I cracked and owned up. Nor what happened when I did so, only that the sun rose the next day, and the one after, with no lasting ill effect. I think I was made to give back to my sisters the pieces of wooden furniture and glue that should have been theirs. In time, they found their way into my dolls' house. In the way of these things, it has become part of family folklore. The story became bigger in the telling, funnier, backlit and metamorphosed into "an event". But the emotion of it remains, the memory of guilt, like a scar.

And the dolls' house itself? It sits, dusty and abandoned like so many childhood things, in my parents' loft. Thebattery-powered lights no longer seem so miraculous, the furniture shoddy and workaday. It all seems so insignificant and inadequate as a symbol of a risk taken and a lesson learnt one endless Christmas Day in 1970.

Kate Mosse's latest novel, 'Sepulcre', is published by Orion