Big families don’t feature much in novels - I mean really big ones. It’s hard to think of a larger fictional brood (Letters Editor, perhaps you’d better brace yourself) than HE Bates’s seven Larkins. The Hegartys in Anne Enright’s stunning new book The Gathering are 12 - Midge, Bea, Ernest, Stevie, Ita, Mossie, Liam, Veronica, Kitty, Alice and the twins, Ivor and Jem. Enright’s narrator is Veronica, seventh from the top, fifth from the bottom, 39 at the time of telling. Veronica dislikes her name, even after a nun explained to her that she was named for a saint who wiped the face of Christ on the road to Calvary and took the very first photograph. To Veronica, her name sounds either like the ointment or the disease.

A Larkin-sized family can seem to represent an abundance of vitality, but a Hegarty-sized one, which could empanel a jury without outside help, is almost the opposite of a family. Catholicism has something to do with large families and the Hegartys are nominally Catholic, but no more than that. Veronica has spent a lot of time over the years watching her father in church: “I never heard him pray aloud, or saw him bend his head, or do anything that might be considered remarkable were he sitting on the top deck of a bus.” Which leads her to conclude that she was right all along in thinking that her parents” reproductive zeal was only a sort of incontinence - they “were helpless to it, and bred as naturally as they might shit’.

So large a family is more like a tribe, with its own rites of passage: “We had a sister Ita who was, even then, the most disliked among us, as perhaps each of the girls were, at the moment their breasts began to grow.” There are compensations, but they seem modest: “The thing is, there was great privacy in a big family. No one got into your stuff except to steal it or slag you off.” Punishment was delivered on a random or statistical basis. “Although my father used to hit his children all the time, more or less, it was never personal. He might slap three at a time and let the fourth go or he might stomp among us with his hand raised as we ran, shrieking, around him.” Even good sibling relationships are similarly impersonal: “Ernest was always nice to me, growing up. We were just the right distance apart.’

Veronica finds, when she communes with others similarly afflicted, that all big families are the same. “There is always a drunk. There is always someone who has been interfered with, as a child. There is always a colossal success, with several houses in various countries to which no one is ever invited. There is a mysterious sister ...’

In fact, there’s more than one drunk in the Hegarty family. They all drink, it’s just that they don’t drink together, and there is one official, certified excessive drinker, Liam, and that is mainly because “a drinker does not exist. Whatever they say, it is just the drink talking’. It is Liam’s suicide which sets the plot in motion. He has drowned himself in Brighton, considerately wearing a high-visibility jacket so that his body would be easy to find. He was only 11 months older than Veronica, which made him in her mind a sort of premature twin.

She registers her bereavement as a physical event: “It is a confusing feeling - somewhere between diarrhoea and sex - this grief that is almost genital.” Veronica has a lot of grief work to do, while the body is bureaucratically delayed in England, and even after the wake and funeral. Enright’s title obviously refers to these family get-togethers, but also perhaps to the process of Veronica’s grieving, as she pulls strands from the past, trying to disentangle what is standard to “the wound of family” and what is particular to the Hegarty history. Which are the first and which the final causes? Suspicions gather like the matter in an abscess.

She senses that the seeds of Liam’s death were sown early, during a summer when their mother was giving birth or having a miscarriage (there’s a whole Larkin family’s worth of non-arrivers as well as the dozen delivered) and the children stayed in their grandmother Ada’s house in Broadstone. Why is Germolene the smell of things going wrong?

Veronica tries to reconstruct Ada’s life from the time she met her eventual husband, in 1925. These passages are almost too good - they’re obviously the work of a professional imaginer, which Veronica, despite her background in journalism, can hardly be. Talent like Enright’s can’t easily be delegated to one of her creatures. There might have been a case for telling Ada’s story impersonally, though the impossibility of Veronica’s ever knowing what sort of relationship Ada had with her husband’s friend Lambert Nugent, however vivid her guesses, is the whole point.

This is a story of family dysfunction, made distinctive by an exhilarating bleakness of tone. There is no sentimentality here, and no quirkiness. Enright may use local words like “bocketty” and “gobdaw’, but her writing is guaranteed to be blarney-free. The humour in it is very close to pain. Veronica is clever, but she knows that cleverness isn’t a solution to anything in itself. Aren’t all the Hegartys clever? “Clever, which is to say unredeemed; earning more or less money than the next person and liable to smart remarks.” Yet she’s strangely good company even at her most negative.

Anne Enright has all she needs in terms of imagination and technique and she’s a tremendous phrase-maker. All that I would timidly offer her is a bouquet of “as ifs” with which to vary her “likes’. The two constructions are usefully different. They point up different structures. In fact they’re like the points on a railway line, sending the sense along one route or the other. When she writes that Veronica’s husband is asleep with “a straining smile at the edge of his eyes, like what he sees in the centre of his blind forehead is so convincing, and fleeting, and lovely ...’, “as if” instead of “like” would announce in advance that the sentence won’t end with “forehead’, which (grammatically) it might as things stand. But then I like to play Fantasy Creative Writing Class, in the way more red-blooded people play Fantasy Football. I’m always thinking of a class where all the students have genius and I get the credit.