Sara picked it up, the sickly taste of anxiety in her mouth. This was not going to end well. Alcohol sharpened the edges of her mother’s personality until it cut her daughters to ribbons.

‘Where’s Brinley?’ she said.

Sara made herself look at her mother. ‘She’s asleep. She was tired.’ She gestured in the vague direction of the camping mattress.

Mrs Carter pursed her lips but did not comment. She glanced around the bedroom.

‘What about Shannon?’

Sara’s mouth dried. ‘She’s in the’ – she coughed to clear her throat – ‘bathroom.’

‘I’ll wait for her,’ said Mrs Carter, putting down her glass. Sara noticed her lips were darkened by wine.

‘She was going to have a shower, I think. She’ll probably be a while.’

Sara kept her voice steady. She was good at lying and had perfected her technique over the years. She knew how to keep a story straight, how not to break under interrogation, and, most importantly, how to protect her older sister. But Mrs Carter’s eyes were watchful and knowing. The flickerings of Sara’s unease deepened into something more primal.

Mrs Carter raised her eyebrows. ‘I see.’

The camping mattress had been made up and laid out under the window. Mrs Carter switched on the main bedroom light. Under its harsh glare, the duvet appeared lumpy and unconvincing, not human-shaped at all.

In three strides, Mrs Carter was across the room and kneeling by the pile of bedding.

‘Don’t wake her,’ cried Sara, who could not bring herself to watch.

Mrs Carter ignored her. Propped in the corner of the room was Shannon’s hockey stick and the older woman picked it up. With as much strength as she could muster, she brought down the weight of the wood on the soft mound beneath the covers. Once. Twice. Three times, she struck it. As hard as a hammer falling. As hard as an iron bar against flesh.

She pulled back the duvet to reveal a dented pillow and Brinley’s discarded clothing.

Caught in a lie like a rabbit in a snare.

Her mother stood up, fluid and elegant, and headed towards the empty bathroom. Sara closed her eyes. Her mind was feeling around for ways she might warn her sister, but panic was whitening everything. In that blank space of fear, she couldn’t think of anything useful at all.

Mrs Carter’s back was to her youngest daughter. With controlled precision, she closed the bathroom door and turned to face her.

‘Where are they?’

Her voice was soft, pleasant even. But Sara was not fooled. Dr and Mrs Carter were specialists in sleight of hand, the art of pretence, the cover story of loving discipline. The Carters were wonderful, invested parents, according to Sara’s school teachers, her violin tutor, Brown Owl, the owner of the village bakery. According to everyone they knew. Except their children.

‘I don’t know,’ she said.