It will take them a while, which is good, because I’ve got more business here. I leave the laptop glowing in the four-wheel drive and take your holdall from the seat beside me. I tiptoe up the drive of 6 Gimble Lane and push the key in the door. To my relief it turns. I thought it would – only a small percentage of me doubted it. Most people neglect details like changing the locks regularly because we are all hard-wired for optimism.

Your mother is no exception. The key turns but there is a door chain stopping it from opening. Fuck fuck fuck. I lean hard against the wooden door and push and push, and finally the cheap metal breaks. I wait for a full minute, hidden back against the wall outside, in case anyone heard the crack, but all is quiet. I know this house; bedrooms at the back, away from the traffic on the road.

I creep into the house I lived in after we married. It’s mostly the same as last time I was here. I hurry through the hallway and push the bag into the cloakroom. Her new kitchen is cavernous and opulent and the low lighting is automatic, so as I pass the doorway it comes on and startles me.

It’s then that I see a pair of trainers under the table and a schoolbag slung over the back of a chair. I turn back to the cloakroom and pull out an anorak and bury my face in it. My daughter. It’s the nearest I have been to her for months.

I hear a movement upstairs. Heavy footsteps. There’s a creak of a floorboard and my muscle memory recalls from when we lived here when we were first married that someone is on the way to the bathroom. I duck into the cloakroom and pull the door closed behind me. In seconds the strip of light below the door disappears and I breathe out. The kitchen is in darkness again and no one knows I’m here.

I wait for the toilet to flush and hear the footsteps on floorboard, tracing them by memory back to your mother’s room. It’s a treasure chest all around me, with my children’s shoes and bags. I open a gym bag and pull out a leotard and pumps. Dirty football boots in another. I hold one of the muddy boots close to me. I’d hoped that they’d kept up with things. These were the minutiae that lined my bigger worries about their health and happiness.

I’d follow them, trying to see their lives. Sneaking around their school and waiting to see them. Peering through the community-centre windows to watch Laura perform her first pirouette. Watching from the sidelines of the football matches in disguise, cheering every time my son kicked the ball. Watching them go to Christmas parties and school trips, all dressed up and excited.