An avalanche of Christmas catalogues has arrived unseasonably early, and my goodwill is already running thin. Not only because I feel strangely compelled to leaf through page after page of bathrobes and “ironic” items, just in case one might yield the Holy Grail of gifts - and I experience afresh the annual anticlimax of the mug which is a tomato and the cat's bottom which, “hilariously”, holds tea towels. But also because my children seize on these catalogues to demand things I would rather they didn't know about.

The John Lewis preview catalogue, while admittedly giving only a taste of what is in store, seems to imply that little girls must be showered with pink trinkets, preferably in pink frilly bedrooms. Meanwhile any self-respecting boy must own battalions of sinister terminators and robotic monsters, preferably black, with eyeless heads or faces of pure evil. These themes are repeated everywhere.

So hideous are some of the boys' toys, so frightening, that slugs and snails would seem a healthier option. But those creatures would come with a health warning, while figures that could have walked straight out of Hieronymus Bosch (I expect copyright has lapsed by now) are promoted with relentlessly cheerful blurb. “Terrifyingly fabulous” is how the Early Learning Centre describes its Tower of Doom castle, marketed to three-year-olds and up, which comes with evil eyes and evil figures, including a skeleton in battledress. For those who do not have children, let me point out that most three-year-olds still suck their thumbs and have a favourite stuffed animal they cannot sleep without.

“Scare your human friends and family,” boasts the product information for the Doctor Who Dalek Hybrid Voice Changer Mask, whose single eye glares malevolently out of a mass of dangling tentacles. “Turns your voice into a Dalek's.” This product is aimed at five-year-old boys. Why do manufacturers assume that five-year-olds are watching Doctor Who, which comes on at 7.30pm?

Even Lego, which has given our family many absorbing hours, seems bent on destruction as much as construction. You leave the gentle realms of toddler Duplo, build some useful trucks and boats, then are catapulted, aged 6 or 7, into a place almost exclusively inhabited by mutant monsters. The Exo-Force Shadow Crawler is a spider-like battle machine that drags along the skeleton of a former prisoner. The Bionicle Barraki Mantax is “a stealthy and deadly attacker who lies in wait at the bottom of the sea”. Anyone for nightmares? What happened to the joy of building something positive?

I meet more and more middle-class parents who have banned toy guns from their houses. “I don't want violence in the home,” they tell me, prissily. Yet some of the same people seem content to fill the vacuum with evil fiends. I have happily bought my boys swords, water pistols and cross-bows. I spent many childhood hours pretending to shoot people with my rifle, which made a deeply satisfying crack when you pulled the trigger. I knew perfectly well that pretending to be aggressive was not the same thing as being violent. In our house today, the pirate sword is not just a weapon: it regularly doubles as a teddy bear's ladder and a rudder in a pretend boat. But the robots and monsters have no versatility. They are designed to look evil. And they are almost universally, explictly, bent on mass destruction.

Maybe I am oversensitive. Maybe Transformer robots are just the modern version of Cowboys and Indians, which, however you played it, usually had a strong story line of good versus evil. You are supposed to side with the Autobot Transformers against the evil Decepticons, led by Megatron, who seek to conquer and destroy. But almost every child I ask thinks that Megatron and his sidekicks, Bonecrusher and Devastator, are much cooler.

These days, storyline is no longer an issue. Now that there are billions to be made from promoting a character across a range of formats - books, films, lunchboxes, hats - it no longer matters which comes first. Disney's bland, humourless Winnie the Pooh is devoid of any scintilla of the wit and wisdom of A.A.Milne. My children do not even recognise him as related to the real stories, which they love. On the other hand, the Power Ranger figurines that my eldest longs for were invented before the movie that accelerated their fame. There is a vague theme of good versus evil. But bad and good are indistinguishable when heroes and villains alike leave trails of death and devastation.

Everywhere you look, baddies are being celebrated. It's fun, it's ironic - for world-weary toy makers seeking the next big thrill. But three-year-olds don't do irony: at least mine doesn't. He simply thinks that the baddies are cool. He would also like a doll's house. But I have yet to find one that is not hideously expensive, which is not also hideously, day-glowingly, pink - which he would shun as “girly”. These perfectly natural human contradictions are not helped along by relentlessly narrow, gender-specific marketing.

Of course boys and girls are different. But it seems pointless to exaggerate the differences to the point of virtually excluding play between them. Faced with having to entertain a girl he didn't know very well the other day, my five-year-old kindly thought of offering her the pink Power Ranger. She felt patronised. He was upset.

I'd like a Christmas without Darth Vader, Spiderman and my own nameless fears conveniently packaged up and reflected in an all-in-one monster that is bound to end up flashing, malevolently, on my pillow on Boxing Day. Is that really too much to ask?

camilla.cavendish@thetimes.co.uk

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