She didn’t see the boy until he was already on her bonnet, his face distorted first by shock and then the impact with her windscreen. And then he was gone, rolling away from her and out of sight.

Where was he? She was going to run over him as well as knocking him down. Her instincts took over and she slammed on the brakes, the car shuddering to a stop. The driver behind was surely going to smash into her now. She braced herself for the impact, but it didn’t come, the car managing to brake in time. She could see the driver, a woman with silver hair, in her rear-view mirror. Her eyes were wide, her mouth open in horror.

But where was the boy? She should get out and see if he was all right, but she couldn’t make her legs move. All communications between her brain and her muscles seemed to have been cut. Her breath was coming in short snatches, as if something had sucked all the oxygen out of the car and she couldn’t get enough to fill her lungs. Her heart was banging so hard in her chest that she could barely hear anything else. But there was something, a little sound in the distance that she couldn’t quite focus on. It was a voice, she worked out. Someone was shouting at her. She tried to concentrate, listen to what they were saying, but it sounded very quiet and far away.

‘Are you hurt? I’m calling an ambulance. Stay where you are.’

It was the woman from the car behind, now out on the road next to her window, mobile phone in hand.

‘Ambulance, please. And police. There’s been an accident. A boy. He just ran out into the road. He didn’t look. He ran out and a car hit him . . . No . . . I don’t know . . . No, it wasn’t my car. It was the car in front of me, but it wasn’t her fault. There was nothing she could have done. He just ran out . . . Yes, I think so. Hang on.’

And then the woman was talking to her again through the window, her voice muffled.

‘Are you all right? Are you injured in any way?’

Suddenly she had to get out into the fresh air. The space was too small. She couldn’t breathe. She scrabbled for the seat belt, clicked it loose and flung the door open, pushing her way out. There were cars everywhere, all stopped and pointing towards her as if she was the main attraction. It felt surreal to be standing in the middle of the road surrounded by cars but without the sounds of engines around her.

But where was the boy? She dropped her eyes, searching for him, and there he was, lying across the opposite carriageway, the wheels of another car stopped just inches from his supine body. The first thing she noticed was that his leg was all wrong. It shouldn’t be at an angle like that. She wanted to bend down and straighten it for him. And then she saw his face. His eyes were wide open and sightless. That was when she knew, without a shadow of doubt, that he was dead. That she had killed him.