I read Shirley Jackson’s We Have Always Lived in the Castle (1962) one summer as a teenager. It’s a work of gothic horror, and a mystery novel. More specifically, it’s a strange, haunting story about a town that fears and is obsessed by two of its residents following the fatal poisoning of their family. I have always thought of it as a book about sisters, about Merricat and Constance, ‘two halves of the same person’. Endlessly self-absorbed, I spent my first reading thinking of my own sister. Our relationship was the most important and the most constant in my life, as we moved back and forth between the homes of our divorced parents. And so, of course, in the heat of the summer, with my sister my main source of company, I felt that this book had been written specifically for me.