‘I am still your maid of honour, aren’t I?’ I said. My hand hovered above the table like a UFO: I wanted to grab hers, but the airspace felt hostile. ‘I know Kitty’s organizing the hen night, but I want to help in any way I can.’

That pained look again. How could she – the functional, together sister – possibly need my so-called help? Shame washed through me like a mouthful of acid.

‘Just say if you don’t want me there,’ I snapped. ‘It’s fine.’

The waiter was returning with a towering plate of dim sum. Sophie looked outwards into the buzz of the busy restaurant, playing for time.

‘Of course I want you there!’ she said. ‘You’re my sister. You’re you.’ The way that those words cracked her voice, cracked me. ‘But I can’t choose between you and Mum. I can’t choose between you and enjoying our wedding day. You must understand that.’

‘Of course I do!’ I said, my hand flying for hers across the food. She let me take it now: there was hope. I had to make this right. Mum’s cold, vindictive stare as she left the flat was still boring into me. I’d have to match her to survive – maybe that was my twisted genetic inheritance. I took a breath.

‘Sophie, I know how it looks. Like I’m this self-indulgent, unstable nightmare who went off the rails when I was a teenager and never came back. But you were too young to understand, and I’ve wanted to protect you from the truth. Because you’re my baby sister, who I love more than anyone.’

Sophie’s wide brown eyes were watery behind her glasses. I kept going, pressing hard against the chink in her armour.

‘I didn’t want to destroy your childhood. You’ve always been so… so fucking happy! And I love that about you. It makes life easier…’

‘My life isn’t some permanent sodding picnic, Rachel,’ she interrupted, but I squeezed her hand and carried on talking. I couldn’t afford to look down before I’d walked the full length of this particular tightrope.

‘Mum and Dad – I’m not saying they don’t love us, or they haven’t tried to be good parents, but… that marriage isn’t what it looks like. How they want it to look. And I was too young…’ A sob rose up, but I forced it down. ‘I know how much you loved Esther, and I’ve never wanted to tell you this, but she was definitely Dad’s mistress. In our house. And when I found out, when I walked in on them, Mum punished me for it. I needed her so badly, and she just – she just chucked me out, emotionally, like I was rubbish. You know how hard on us she can be. It was that times a hundred till I went to university.’