I close his door behind me and run downstairs, ready with my excuse for being here, my unjudgemental smile firmly in place, but it isn’t Anna standing on her doorstep, looking sheepish. It’s Detective Inspector Marsh. If he’s surprised to find me here, he doesn’t show it. I look behind him, but I only see his car, double-parked. No Anna getting out of it.

‘I’ve just been on the phone to the police,’ I say. ‘Has something happened to Anna?’

He follows me into the kitchen, and I shut the door so that Kai can’t hear. I fill the kettle, but he doesn’t want anything. I want to do something with my hands, but I don’t want to appear nervous, so I lean against the counter and hook my thumbs into my jeans pockets.

‘Why are you here, Ms Trelawney?’ he asks.

‘Her son called me. He was worried because she hasn’t come home.’

‘Why didn’t you alert the police immediately?’

I frown. His question feels like an accusation. ‘I assumed she would be back. I didn’t want to get her into trouble for leaving Kai on his own if she was going to reappear at any moment.’

‘What time did he call you?’

‘Around one o’clock.’

‘So you waited for, what, two hours?’

‘I didn’t want to turn this into something it wasn’t.’

He peers through the glass screen door into the small garden. ‘Where did she tell Kai she was going?’

‘She didn’t. He got up in the night to go to the loo and noticed that she wasn’t in bed. That’s when he called me.’

I’m starting to tremble inside. Of course I should have called. What stopped me? Was it because I’m suspicious of Anna and wanted to spend some time snooping round her house? I glance at Marsh’s face, but it’s impossible to read. He looks tired too.

‘You didn’t think it was odd?’ he says. ‘After going through the same thing yourself so recently?’

‘I didn’t relate the two events. I don’t know why not. I assumed Anna had told him a white lie; that she was meeting someone – a date. She does use online dating sites.’

‘Is she the type to go out without arranging childcare?’

‘I don’t know. I haven’t known her very long. Will you please tell me what’s going on?’

He picks up a sheaf of papers from the table and looks through them. It’s mostly stuff from school: newsletters, sports slips for her to sign. He puts it down.

‘When did you last see Anna Foreman?’

I try and remember but my brain is all over the place. Since Nick left, time has stretched, occasionally snapping back and catapulting me forward, but mostly the days have felt like weeks.