‘I’m sorry,’ Emmy says. ‘I’m sorry, Mummy. I’m sorry.’

I slump down on a rock, stunned. I do not see my mother. I have never allowed the children to see my mother because I do not believe she’s earned the right to her grandchildren.

‘Mummy, please . . .’

I look helplessly at my daughter’s ketchuppy face. As a child I thought my mother would love me because that’s what mothers do in books. I struggle with indignant tears. How dare she think she can just slip into their lives, guilt free. How dare Dad let her?

‘Grampa said you’d be angry,’ Jack ventures.

‘I’m not angry with you, either of you, I’m not.’ I smooth my hand against his cheek, then grab hold of Emmy and squeeze her. My poor little Emmy who can’t keep a secret. Emmy, who has said nothing for all this time . . .

‘Mummy, stoppit.’ She wriggles free. ‘Look!’ She twists my head and I stare, puzzled, into the night-time haze until I see them, just visible, two headlights dipping in and out of view as a car rumbles round the mountain.

‘Oh, thank you, God.’ I jump up.

‘Yes, thank you, God.’ Emmy puts her hand in mine. I put my other arm around Jack’s shoulders and we stand in the middle of the road together as the headlights grow brighter and rounder and bigger and closer.

The children sit wordlessly in the back of Duval’s truck. I take sips from the water bottle, my feet nudging Taco’s back, while I try to think of something to say. Since the Taco incident, conversation between Duval and myself has become even more of a tightly scripted affair, based around the tangibles of light fixtures and electrical sockets, so after my ‘thanks a lot, very kind of you’ and his ‘no trouble’ we both fall mute. It’s dark outside the window. The skeleton outline of the mountains just visible against the sky. In the Orkneys, I think, under this very same sky, people could be staring at the Northern Lights.

‘What are you going to charge people to stay in that place of yours once it’s finished?’ Duval’s voice breaks the silence.

‘I don’t know,’ I answer, surprised at the direct question. ‘Couple of hundred dollars a night, maybe.’ There were health retreats and spas all over the west of America. I’ve done my internet homework. One, on the outskirts of Taos, New Mexico, offered peace, serenity and cyanide baths for $3,000 a week.

‘Uh-uh. So people who drink too much, smoke too much, eat too much, will be able to pay even more to feel better about themselves.’

‘There’s nothing wrong with people who have money and are not starving,’ I say coolly.