No. That’s not what happened. When I asked him if he could think of a reason why Billy would do that he didn’t actually answer the question. He said something about fathers and sons clashing and reminded me that he hadn’t got on with his own dad. Then he asked me if I was accusing him of doing something to Billy. He deflected me. Twice. I asked him twice and he changed the subject both times. He didn’t actually lie.

A new thought occurs to me. Billy was doing an art project at school. That was why he’d borrowed it in the first place. When was that? I pull open the junk drawer and rummage around in the bottom where I keep the family calendars. I never knew what to say when the kids asked me what I wanted for Christmas so I’d always say a calendar because they were cheap and useful and it meant I wouldn’t have to smuggle overpriced bath-bomb sets that brought me out in hives into the charity-shop bag on Boxing Day.

Mark’s always teased me about keeping the old calendars. ‘You’re turning into a hoarder like your mum,’ he’d joke as I’d slip another one into the drawer on 1st January after I’d copied everyone’s birthdays and anniversaries onto the new calendar. I didn’t pay him any attention. I liked looking back on all the things we’d done each year: the kids’ swimming lessons, the birthday parties they attended, the holidays we took. They were all recorded in my small, neat handwriting. Billy and Jake hated it when I pumped them for information about exam dates and coursework deadlines.

‘Stop being such a control freak, Mum,’ they’d chorus.

That accusation again.

I pull out a wad of calendars. Last year’s is on the top. I flick through it, find nothing and then start again, reading each entry carefully.

5th January – Mum’s birthday.

16th January – Parents’ evening (Billy).

21st January – Dentist appointment for Jake and Billy.

30th January – Car MOT (mine).

I flick over the page.

4th February – Caleb’s birthday.

17th February – Doctor’s appt (Mark).

24th February – Billy GCSE art DEADLINE.

There! There it is. The end of February. And we went to the pub to celebrate my birthday on …

I flip the pages over and stab the date with my finger. Sunday 31st August. At some point between 24th February and Sunday 31st August Mark went to the pub, nearly lost his job and kissed Billy’s teacher. Stephen said it happened last summer but he didn’t say when. I turn the page.

5th/6th July – Mark to London for annual general meeting

2nd/3rd August – Mark conference

13th/14th September – Mark training weekend

25th November – Mark sales team meeting