Complete Surrender, by Dave Sharp

Another child in his time

Like those cowboy films that only kick into gear when the tall, lantern-jawed stranger strides retributively towards the dangling double doors of the saloon, so Complete Surrender has to wait until the 15th of 23 chapters for anything momentous to happen. This is not to deny the human interest of Dave Sharp's saunter through his Thames Valley childhood, and a married life that began as the Swinging Sixties burst into bloom. But it is not until the author wanders into an Oxfordshire wine bar in early 2002 to meet his long-lost brother, Ian McEwan, that a succession of money shots start to snap reliably into place.

The parentage of the brothers McEwan, confirmed to both by a Salvation Army lieutenant shortly before the meeting, crashed into the newspapers last year. Younger sibling Ian (born 1948) had always assumed he was the solitary fruit of his mother's second marriage to an army sergeant-major, David McEwan, after her first husband, Ernest Wort, died in action in the Second World War. In fact there was another son, born out of wedlock in 1942, while Wort was away on military service, his birth concealed from his putative father and wiped from the family slate by his transfer – on Reading station – to a couple who had replied to an advert in the local paper.

It is an extraordinary story, yet one of the inferences both from Sharp's memoir and his brother's thoughtful introduction is that most family histories, if investigated, will turn out to have these bygone wraiths capering mournfully in the woodshed. As for Sergeant-Major McEwan's separated sons (the sub-title about "a family's dark secret and the brothers it tore apart at birth" is misleading; how can you tear apart two people who don't know of each other's existence?), Ian enjoyed a peripatetic childhood, courtesy of his dad's army postings, went to a state boarding school and university and became a distinguished novelist. Dave worked as a bricklayer, supports Reading FC and has a weakness for the mildly sarky aside.

As a piece of drama, Dave's slow but purposeful trip along a path to the half-brother and sister of his mother's first marriage, wide-eyed Ian and even old Mrs McEwan (sadly in no state to recognise him) shortly before her death in 2004, can hardly fail, even if some of the dialogue clunks like a wicker gate. But what about the story of Dave's life, that series of contrasts and comparisons on which, after all, the book relies on for its ballast? This is full of fascinating detail: the privations of the Fifties childhood redeemed by its elemental freedoms; the hospital matron who, as the young father quits the premises with wife and newborn child, snaps: "Remember, six weeks – don't be an animal".

Yet the lurking presence of the amanuensis, in this case John Parker, stirs faint unease about the purity of some of the memories on display. Did Sharp's recollections of, say, Churchill's funeral or the Moon landings spill unchecked onto the page or were they prompted, however indirectly, by his ghost?

There is, of course, another book waiting to be written about l'affaire McEwan. More than one critic has noted that McEwan's novels are simply stiff with children who have either been abandoned (The Cement Garden) or vanished from their parents' grasp (The Child in Time), and hazarded the existence of a vast reservoir of "secret" knowledge periodically escaping from its mental vault. This will probably take a psychologist to construct. In the meantime, Complete Surrender is an intriguing social document.

DJ Taylor's 'Bright Young People' is published by Chatto & Windus

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