Call me innocent, but before this year’s book festival, I’d never heard of covert incest, and it might well have been a new one on most congregations at Edinburgh’s Central Hall too. But there it was on Wednesday afternoon, one of the themes in Love Marriage, Monica Ali’s first novel for ten years, and it was back again yesterday as Patrick Gale talked about his latest, Mother’s Boy.

In both novels - and indeed generally - no inter-family sex is involved: covert incest is what happens when a parent looks to a child for the kind of emotional support that a partner would normally provide. In Love Marriage, that meant overbearing upper-middle-class feminist icon Harriet, who is rather too close for comfort to her son Joe, who is about to marry into a British Asian family. Ali’s characterisation is always far deeper than mere stereotypes, and she had begun by writing separate stories about each family, but already you can see the outlines of a satisfyingly tangled web.

Addressing the question of why this his her first novel for ten years, Ali mentioned that some of that time had been lost to depression, which she equates with the lack of confidence that underlies writer’s block. Hopefully, the warm response to her new novel, echoed by similar reactions from teens studying Brick Lane at school, might have helped in this regard. She is also, she revealed, adapting Love Marriage for television and contemplating a sequel.

As its title suggests, mental health issues are to the fore in Kevin Bridges’ debut novel, The Black Dog. Unexpectedly, it wasn’t the only link between the events. Both writers gave exactly the same advice about the importance of leaving a good scene unfinished overnight while admitting how hard it is to do so. The rush of being immersed in writing is, said Bridges, even greater than doing standup, though there are similarities; working from a kernel of what he knows is a good laugh, he has to set the scene live, driven by adrenaline, in front of a crowd. “A good comedy crowd,” he said, quoting Jerry Seinfeld, “helps you write. A tough one helps you edit,” adding with his trademark grin, “So I do my writing in Glasgow and my editing in Edinburgh.”

Back, though, to covert incest. Or rather to Charles Causley (1917-2003) the self-taught working-class Cornish poet, whose mother loved him too much for his (or her) own good. Causley was highly esteemed by contemporaries such as Larkin and Hughes but is now facing neglect, from which Gale’s new novel aims to redeem him. “He is falling off the curriculum for being stale, pale and male,” said Gale , “but if I can show he is gay as well, that might rescue him.” Gale is honest enough to admit that he can’t prove the extent of Causley’s sexuality, but that shouldn’t take away from what sounds like a fascinating novel. Asked by an audience member to read Causley’s poem Eden Rock, he took out his phone and did so. It’s a short poem, but deep as a lifetime. Do check it out.

Finally, still on the topic of things I didn’t know about, here’s a factoid from yesterday’s event with Devi Sridhar. Before it was shot down as being absurd, in the early stages of the pandemic one SAGE adviser made the suggestion that Covid should be left to rage unchecked in England and all its vulnerable people be sent to Scotland. Imagine the reaction here, I couldn’t help wondering, if it had been the other way round. David Robinson

Edinburgh International Book Festival round-up: Monica Ali | Kevin Bridges | Patrick Gale