Left to pick up the pieces, sleep-deprived and consumed by worries for the future of his son, Craig had struggled and stumbled through those early months: the surgery, the pitfalls and problems, as well as the moments of sheer fatherly delight. Writing about it helped him deal with the complicated mess of emotions that he experienced, and when he ran the idea of a weekly article past his editor, the column was duly commissioned. By sheer serendipity, Frankie, a freelance illustrator, was asked to provide the artwork for his page each week and so their relationship began – as words and pictures initially, two people doing their jobs. But quickly, and like millions of other women around the country, Frankie found herself falling for funny, capable, wonderful Craig and his devotion to his boy, looking forward to receiving his new instalment every week, and cheering him on from the sidelines as she illustrated each piece. They’d met at the newspaper’s Christmas party and had sought each other out, exclaiming, ‘I love your work!’ in drunken sincerity, before ending up, much later on, knocking back whisky in a nearby bar and telling one another their life stories. She’d moved into Craig’s flat six months later, and when Fergus had started talking and called her ‘Mumma’, neither of them had stopped him. It was, all things considered, the happiest of happy endings.

And it was enough, Frankie thought now, as she sat down on the carpet and Fergus talked through his elaborate new track layout with her, and chose which engine she was allowed to have (the worst one with the wonky wheels, obviously). Forget Harry Mortimer and his shocked expression, forget his dagger-eyed wife – to hell with the lot of them, Frankie told herself fiercely. This small lovely family of hers right here was enough. This was plenty.

Back in Yorkshire, the Mortimers were all struggling to come to terms with the shockwaves caused by Harry’s announcement. Stephen was driving his parents to the airport, a freezing silence splintering the atmosphere inside the car, despite his Herculean efforts to make conversation. Whenever he glanced across at his dad in the passenger seat, it was like looking at a stranger. How could he have done that to Mum?