Rose drives, Aaron in the passenger seat. He holds her phone in his hands, following a route. They drive on smaller roads. She has never been on a motorway.

‘Knock knock,’ he says.

‘Who’s there?’

‘Boo!’

‘Boo who?’

‘Don’t be such a baby!’ Aaron crows.

She can only spare him the slightest glance. She needs all her concentration for the road. But she has to look, has to check. His voice is just like it was, but the rest of him, no. He’s grown.

‘Can I smoke?’ he says.

She shakes her head.

‘Please?’

She shakes her head.

‘Why you such a moody bitch?’

She frowns at the road.

‘Sorry,’ he says. And then, ‘Do you remember when we drove to the lake?’

She remembers. A friend of their mother’s took them – Aaron was six, and she was nine. The lake had picnic tables beside it. On the way, they listened to the radio, and they sang along to ‘American Boy’. The shore of the lake was a thin pebbled strip, and you could see a mountain on the other side. They had a stone-throwing competition. They watched other kids go in the water, but they didn’t have costumes, so they rolled up their trousers and stood in the water. Their mother’s friend – they were never told his name – brought a picnic. He had Hula Hoop crisps and ham sandwiches and bananas and digestive biscuits.

‘Do you remember the biscuits?’ says Aaron.

‘Yes,’ says Rose. She remembers the way her mother’s friend looked at them while they ate.

The road winds along a river valley. Trees arc over. Houses cluster in groups along the sides of the road then melt away. They pass through a town. The town disappears again.

‘You’ve not got enough battery.’

They need a charger and they need petrol. Rose has twenty pounds.

They stop at a petrol station. Rose goes in to check about the charger. It costs £5.99. She goes back to the pump and puts in just under fourteen pounds’ worth. She is left with six pence.

The man serving is old, with spiky white and black peppered hair and a face that is lined and sagging. He looks at Rose, his watery eyes flicking across her, back and forth.

She smiles. She finds it hard sometimes to see whether people feel sorry for her or want to fuck her.

‘What about Jack?’ says Aaron.

There didn’t seem much point in hiding him. She doesn’t know what will happen when he’s found. If he’s found. Maybe they would think it was an accident.

She knows they won’t think it was an accident.

The only thing she knows for certain now is that Aaron will not be OK. The thought is a thrum of anxiety at the back of her mind.

She knows this will end badly. But for the moment, she keeps driving.