Two days later, however, the run of good times ended. Connor was back in the ensuite, squirming and groaning.

He returned to his diet of poached chicken and baby vegetables, his suspicion of fibre and sugar, his hyper-vigilance regarding toxins. Strangely – so strangely I didn’t feel I could mention it to him – the smell of his stool, or at least what was left lingering in the bathroom, was different. I didn’t realise I had known his smell, but I did, and this wasn’t it. This wasn’t a stink of ours. This was the stench of an interloper.

Not long after this, Connor called me at work. I declined the call and texted him: I’m in a meeting.

I wasn’t in a meeting. I was staring at a page of someone else’s equations, looking for errors.

Urgent, Connor wrote.

‘For fuck’s sake,’ I said to no-one in particular, and went into the corridor to call him.

‘I’ve just stepped out,’ I said when he picked up.

‘It’s Samuel,’ he said.

‘Oh Christ.’ I made my voice a whisper. ‘Did he drop his pants?’

‘He – what? No! God, why would you say that?’

‘I don’t know.’

‘No, he’s had a fall. He’s fine, he’s fine, I’ve picked him up. They wanted us to come in for a conference, but it’s fine, I’ve handled it.’

‘A conference?’

‘I didn’t think it was necessary.’

‘What kind of conference?’

‘With the school.’

I gave him a moment to provide me with a more complete answer. When he didn’t, I said, ‘The school? And who else?’

I heard him exhale.

‘And Deidre Moss.’

I closed my eyes, felt the fury swirling in my body, saw the inside of my eyelids turn red.

‘It’s that little cunt of a daughter of hers, isn’t it?’

I was enjoying myself.

‘What the fuck’s she done this time?’

Connor’s voice was flat. ‘He says she pushed him off the top of a slide.’

‘You don’t believe him?’

‘I think it was an accident.’ He paused. A long pause. ‘You know what he’s like.’

I was silent for a second, winded almost. I thought of all the effort I’d put into not only making Samuel, but maintaining his existence. No-one, not even Connor, had any concept of the work it took, the exertion, the sacrifice, the tedium, the indignity. How dare he?

‘Fiona? You there?’

‘I’m here.’ My voice was calm.

‘I’m sure it was just an accident,’ Connor said again. I pictured him rubbing the back of his neck, a self-soothing gesture that never failed to rile me.

‘Is that what you’re going to say when we’re lowering his little casket into the ground?’ I liked the sound of my voice: cool, controlled, an octave deeper.

‘Fiona —’