The first thing that Mum says when she comes back is, "I'm sorry I shouted at you." She is clutching the edge of the door and swaying. Soft and floppy and not quite looking at me. Looking through me. Grinning wide and slow. The smell of her is terrible. It comes into the cottage with her in a big, bitter wave. Sweat and pee.

I tell her it's okay and she goes past me and flops down on the sofa. She's so limp, arms just hanging. "I'm sorry about... everything else too," she says. I tell her that's okay as well. Everything is okay. She smiles, nods, still grinning. A big, big smile that shows all her teeth. She isn't angry anymore. Not even a little bit, and I'm grateful about that. I want to know where she went.

I tell her I was good while she was gone. I tell her that I shut the door and hid and ate some soup and watched some television. But as I'm telling her all this I notice that she's asleep. I'm kneeling on the floor beside her. It's night again, the world outside dark and the cottage cold and I'm wearing my coat and hat and scarf and gloves even inside.

For a moment it all feels very, very wrong. Like it's not her at all. I'm terrified of that - that I might have just allowed in some other thing that looks like her. Some monster that isn't her at all but speaks with her voice and grins and grins and is soft and not angry and not alive at all, like she is, like she always is, and that it's inside the house with me now and it still looks like her and there's no way of telling and there'll never be any way of telling.

I get up very slowly and move very slowly so as not to wake her and I sit down on the other sofa and pull my coat tight around myself. I watch her. Sleeping. Just sleeping. But she looks different now. I can't tell how but she does look different.

Suddenly she jerks. Right up off the sofa. It scares me so much I bite my tongue. But Mum is clutching the edge of a cushion and she's being sick. A lot of it, rushing out of her mouth and down her coat and down the side of the sofa. One big dark rush of sick. And then she falls back onto the cushions, and groans once, and then she's asleep again as if nothing had happened.