DEATH AND BEREAVEMENT have always been part of great children's literature; yet part of the charm of the genre is that it offers readers hope. Even if Sara's adored father will never return in A Little Princess, and Ginger is carted off to the knacker's yard in Black Beauty, our heroes and heroines survive, their suffering acknowledged and their wisdom won.

Recently, however, a different kind of novel published for children has been gaining ground. It's a novel in which the hero or heroine dies, either through murder or through mortal illness. Given that our children are, according to surveys, the most depressed in Europe, and that parents are currently being terrified by a wave of teenage suicides, you might think that novels of this kind would not be popular.

Far from it: this year's Costa prize for children's literature was awarded to Ann Kelly's The Bower Bird (Luath Press, £6.99/offer £6.64), about a precocious young girl dying of a heart condition. Last week, the Waterstone's Children's Book Prize was awarded to Sally Nicholls's Ways To Live Forever (Marion Lloyd, £7.99/£7.59), about a young boy dying of leukaemia. Last year, Jenny Downham's Before I Die (David Fickling, £7.99/£7.59) was about a 16-year-old girl working her way through a list of experiences she wants to have (including losing her virginity) before leukaemia gets her.

A persistent bestseller among adolescent girls is Alice Sebold's The Lovely Bones (Picador, £7.99/ £7.59) about a murdered teenager looking down on those she knew when alive. Grim-lit, long the preserve of adult fiction, has entered that of children and teenagers.

This presents the parent, and the critic, with serious problems. Are there certain subjects that should remain taboo below a certain age? Certainly, we accept this in film, TV and computer games. Why not in literature?

Francis Spufford rightly described books as “mood-altering drugs” in his wonderful autobiography, The Child the Books Built. Far from seeking out tales of woe, while growing up with a terminally ill sister, he says frankly that he read “to banish pity”. The books he loved were the kind that unimaginative adults dismiss as escapist - The Hobbit, CS Lewis's Narnia books, The Silver Sword, Laura Ingalls Wilder's Little House series - stories in which bad things happen, but are modified by the essentially life-renewing pattern imposed by story.

Meg Rosoff, whose How I Live Now is an example of this, points out: “There's a huge difference between a book in which Little Nell dies and a book entirely devoted to Little Nell's experience of dying. I'm extremely wary of the possibilities for sentimental exploitation inherent in the subject of death - the process of dying is brutal and ugly and terribly sad, and is not assuaged by the dying person losing his/her virginity beforehand (as if!).

“And then there's the very worst sentimental crime - the book narrated from beyond the grave, as if some perfectly nice world exists out there to make the experience of dying not so bad after all. Death is a perfectly valid subject for literature to embrace, but like nudity in film, should be there for a reason, not just to make the reader weep.”

Weeping, however, seems to be what young readers are now hungry for, once they become sophisticated enough to despise Harry Potter.

Marion Lloyd, the publisher of Ways to Live Forever defends the novel by saying: “Death is now such a taboo subject in our society that we are scared to talk about it. A child like practical, 11-year-old Sam, terminally ill but unencumbered with emotional baggage, and expecting there to be a factual answer to every question, simply demystifies the process of dying and makes it unscary. He's interested in mortality, not in grief, and his matter-of-fact voice is often funny, and extraordinarily uplifting.

“Reading good and honest stories about things we can't bear to think about in real life is one of the best and safest ways for all of us - adult or child - to cope with our fears. In [Myra Bluebond-Langner's 1978 study] The Private Worlds of Dying Children the dying children that the author worked with, aged 4 to 9, would ask for the chapter in Charlotte's Web in which Charlotte dies to be read to them over and over again.”

Yet there is an essential difference: Charlotte dies, but both her children and Wilbur the pig live because of what she does. Her death is seen within the context of triumph, and love. Nicholls's brave, sparky, inquisitive hero just dies. The novel, partly because it is more honest, offers no redemption other than memory.

“You're allowed to be sad, but you aren't allowed to be too sad. If you're always sad when you think about me, then how can you remember me?” are Sam's final words. One feels a story of this kind is less for children than for fearful, mawkish parents - or self-dramatising teenagers screaming: “You'll be sorry when I'm dead!”

The best children's fiction, from Babar to His Dark Materials, accepts death and embodies it through an awfully big adventure, which returns the hero to life and happiness. There is no more subversive ending than the fairytale one that “they all lived happily ever after”, and no ending more ardently desired by all readers. It would be a thousand pities if children's publishing, so long the complete opposite of grim-lit, forgets this.

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