WITH me, it’s my Auntie Shirley, and the one bit of her life that we never knew about until we saw a photo of her looking at her wedding ring and standing next to an impossibly handsome Polish soldier in a strange wartime town. With my wife, it’s her Auntie May, in East Cork, who pretended almost to her dying day that she was her son’s elder sister.

I’m guessing that most families have secrets like that, and know all about the shame that pushed those photos deep into bottom drawers, or how the neighbours’ tut-tutting forced masses of our ancient or dead relatives to lead occluded lives. Yet sometimes, if the links weren’t made, the photos destroyed or the gossips sidelined, they got away with it, and their secrets were buried with them.

That’s what happened with Brian Johnstone’s parents Gilbert and Bea. When they died in 1976 and 1998 respectively, they were the epitome of Morningside respectability. None of their neighbours or golf club friends knew about Gilbert’s first marriage or the daughter it produced before it ended in divorce. Bea’s daughter, the result of a wartime fling before she met Gilbert, was another secret. Only after Gilbert and Bea’s deaths did Johnstone and his brother discover that they had two half-sisters as well.

The National:

Johnstone is not only a poet but a great proselytiser for poetry, co-founder of both the StAnza Poetry Festival (of which he was artistic director for 10 years) and Shore Poets, which bills itself “Scotland’s leading platform for live poetry”. And yet this isn’t what one expects a poet’s book to be: it doesn’t distil distant memories with linguistic precision so much as wander around them in an confused daze.

To do much more, he implies, quoting memoirs by Hilary Mantel and Charles Ferneyhough, risks inventing a past that never happened.

But if there’s a bit of a hole where the narrator should be – no clear tracking, for example, of his own transformation from private school blazered conformist to the young rebel who found his five-bedroom Morningside home “a sterile environment I was increasingly determined to flee” – his portraits of his parents have a much clearer focus. His mother, Bea – who came from a moneyed family in Aberdeen and married beneath her – comes across as a four-square Caledonian Hyacinth Bucket – sorry, Bouquet.

Writing thank-you letters to aunts in Glasgow, for example, he was made to put “Renfrewshire” as the last line of the address because Scotland’s biggest city was obviously – like wearing jeans, swearing, watching ITV, listening to The Navy Lark, eating ice cream in the street or playing near the tenement he was born in – too “common”. Curtains had to be not quite fully opened lest neighbours think they were too poor to have any. Even when he was a grown man, Bea’s writ still ran: no, of course he couldn’t park his second-hand former postie’s van outside their house, and if he was going to prune the roses, could he at least not do so while listening to the – heaven forfend – transistor radio?

Some of these snobberies are so absurd as to defy belief – I’ll let older readers enlighten me on why a plain loaf was “common” but a pan loaf not – but some caused real and lasting hurt. Bea’s shame at marrying a divorced man was a case in point. Even though the Church of Scotland had no problem with such marriages, the neighbours might. So nobody could be told that Gilbert had been married before, and that he had a daughter. And – cruelly, hypocritically – nobody, starting with Bea’s two sons, was. Only one secret could possibly be buried any deeper: that, during the war, Bea told her parents the Air Ministry needed her to work in Newcastle. They didn’t. But it was a good place — not too near, not too far — for an unmarried Scottish girl to go to have a baby.

Straight away, you can see the fog from which this book is fashioned. Bea isn’t Hyacinth Bucket/Bouquet at all, but is now beyond all questioning. Gilbert mightn’t even have known about Bea’s baby, but he knew fine well he had a daughter, because until she was four and her mother divorced him for another man, he doted on her. So when Gilbert insisted, as he often did, that he, Bea, and their two sons were “four of a family”, he knew he was lying, even if it didn’t seem like that in his heart, because he did love them.

That, then, is the story as the book opens in October 1998. There’s a telephone call. Bea’s secret daughter — who was adopted just after birth — is in Scotland and has heard about her mother’s death. And Brian Johnstone’s world is about to be rocked for a second time.

It would be too much of a spoiler to reveal what happened next to Gilbert and Bea’s two daughters. What happened to Johnstone is that he had to rethink his whole childhood. In the resulting memoir, there’s too much repetition, the poetry he uses to find his way into the past mirrors the text too closely, but the book is saved by its humanity, wisdom and love. Johnstone isn’t settling any scores with his parents, because he fully realises that they were creatures of their time just as much as he is of his, and that his own late 60s idealism and revolt against conventionality might have had a few blind spots too.