For Mack, fatherhood was having a picture of the boys in his wallet; it was wrestling matches and water fights, for as long as he felt like it. He was the Mighty Daddy, the fun parent, who still got to go to football matches and stag weekends and drinks with his mates, assuming all the while that Olivia would be there to hold the fort in his absence. And to be fair, she had gone along with this division of labour initially: they both knew she was so determined to be a good mother to the boys that she wanted to be there for them for every night-waking, every feed, every cry. Call it atonement, call it proving a point, she was dogged in her belief that this was her work, the least she could do.

Until she realized just how hard it was anyway, how utterly exhausting. How broken she was starting to feel. Was it pride or embarrassment that kept her from telling Mack she was struggling? Or sheer maternal guilt? Whichever, he didn’t seem to have noticed her feelings of failure.

His parents didn’t help matters, either. They were up in Aberdeenshire and had traditional ideas about child-rearing, namely that it was solely the preserve of a mother and certainly not to be farmed out to any third parties, even the child’s own father. ‘Don’t tell me she’s got you changing nappies,’ Olivia had overheard her mother-in-law exclaiming with horror the first time they’d come down after the boys had been born. ‘For heaven’s sake! When you’re out working hard and earning all the money for the family, as well. Whatever next?’

Like Olivia was lounging around eating peeled grapes all day, like she wasn’t working hard. There were times when she looked back on her old job in the university library and it seemed an oasis of calm concentration, practically a holiday, compared to her current job as a mum. Sometimes she could weep for that civilized life of politeness and order, of lunch-breaks and set hours, where nobody was fighting or throwing things or bellowing urgently that they needed the toilet. To think that before the boys she had taken such luxuries for granted!