Charlie has already found his way to the centre of things, handing his present to Molly along with the other kids. Seeing him next to the other children, I realize he must have had another growth spurt. He’s one of the tallest among them now. His hair shines under the lights. We washed it properly in the bath last night, for the first time in what felt like a while. He knows these children: they are his classmates, his friends. It’s totally natural for him to fit in.

I find myself standing next to Martin and Sally. My eyes feel dazzled by all the spotlights in the ceiling. We’ve each been given a slice of chocolate cake on a paper plate. It looks huge, dark and sticky, like something I could fall and get stuck right in, and the paper plate feels almost too flimsy for the weight. When I take a bite, the burst of sugar makes my teeth ache. I don’t think I’ve been brushing properly of late. But the cake is delicious, it really is, and I’ve almost eaten the whole thing before I know it.

Martin and Sally are talking about something, a television programme they both saw last night, some adaptation of a Harlan Coben novel. Their voices sound exaggerated somehow: Sally’s a high-pitched flickering, and Martin’s very loud, booming in my ears. My mouth is too full of chocolate sponge for me to speak, but I look back and forth between them, nodding and smiling.

It’s lovely to be here, it really is. I’m so grateful to Molly’s parents for inviting us.

Now Molly’s mum is setting up a game of musical chairs. The chairs screech as she drags them across the living-room floor to line them up. All the colours and the movements, it looks like something from a carnival parade. The music from the stereo seems to come from all around us; the whole air seems to vibrate with it. I smile and move my head and nod as Sally and Martin continue talking. Now Molly’s dad is coming over to join us. He looks so like Molly, lanky and tall, there’s no way you could mix up who he is. He holds out a hand to me – only to me, because he already knows Sally and Martin, I realize.

‘Molly seems very taken with your son,’ he tells me as I shake his hand. I can feel Martin and Sally both looking at me. I swallow the chocolate cake that’s filling up my mouth. ‘Oh,’ I say, smiling brightly. ‘Does she?’

He’s very tall, Molly’s dad; I feel like I’m tipping backwards as I look up at him. ‘They sit next to each other at school – did he say? She tells me he has been very kind to her. She can be quite shy, and of course, she’s new here.’