She tiptoed along the landing and pushed against it. The room was in darkness but she could see enough to know that Shannon wasn’t in there. She switched on the light.

The bed was empty but the floor was covered with scraps of paper. Sara crouched to retrieve one. It was covered in Shannon’s handwriting: The Habsburg dynasty was . . . She grabbed another one: . . . life cycle of a frog. There were hundreds of them, all written in black ink on lined paper, all jagged around the edges, where they had been torn up. Her sister’s homework – all of it – had been destroyed and scattered across the floor like twisted confetti.

Her sister’s diaries – at least four of them – were strewn across the carpet too, but there were no words between the hard covers, just stumps of paper where the pages had been ripped out.

Their father’s handiwork.

As she was deciding what to do next, she caught the groan of the staircase, and a few seconds later, sensed movement behind her.

Shannon was standing there, a glass of water in one hand, the other tucked behind her back.

‘Did Richard . . .?’

Sara indicated the mess on the floor but couldn’t bring herself to finish the question. The expression on her sister’s face told her everything she needed to know.

Shannon still looked like her sister. She had a mole on her cheek and white-blonde hair and a mouth that was wide and full. But a blind had been lowered. Her eyes were dead, nothing behind them to power their winter-blue light. Her lips were set in a line, no smile twitching at their corners. No frown or anger. No sadness. An absence of emotion, of feeling. Of anything.

She was a husk, the life sucked from her.

A fury began to rise again in Sara, burning her up like a fever. ‘Shannon.’ She shook her shoulder, trying to provoke a response. ‘Shannon.’

But her sister did not reply. She stood alone, fingers curled around her drink, other hand tucked away, and stared through Sara as if she were made of glass.

Sara took a step towards her, to try and coax her back to bed. But Shannon recoiled, widening the distance between them. The younger girl’s hand brushed against her sister’s arm. Her skin was cold and pale. The bloodless ghost of a twelve-year-old.

‘Shannon, you’re scaring me.’

She was pleading now, urging her sister to show herself, to make a joke or whisper a secret, or even gaze at Sara with disdain. But Shannon was lost in a distant land and Sara could not reach her.