She took a breath. ‘I would like to stand up, please.’

Fairfax nodded. Camilla got to her feet and stretched her arms. She moved away from the table a few steps.

‘I have mentioned our nanny, Eileen Braithwaite. She helped with the birth, acting as midwife, and she played along with the secret.’

‘Go on.’

‘To avoid a scandal, Adeline was known as the daughter of Leonard and Mary Estelle, and grew up believing that was the case. I confess, in my youth, I tended to forget her true parentage. I never thought of her as my niece, only as my younger sister. To this day I think the same. And I was happy with that relationship.’

Hobbes stood at the glass, taking this in, willing Fairfax to ask the right questions. He wanted to be in the room, to engage with the emotions, but knew that Camilla might easily close up into her shell. And so he listened.

‘There is an element here,’ she said, ‘that is very important.’

Fairfax asked her what that was.

‘We were brought up as a theatrical family. We were encouraged from an early age to view life as a play, and ourselves as players, or actors, that by following this path we would always be in control of our lives, always be the masters of our fate, and never the victims of circumstance. Everything flows from that notion, which raged strongly in Leonard and in Mary Estelle. It was the guiding force of the house.’

‘I understand.’

She nodded. ‘So this idea, of a grandparent playing the role of a parent, came easily to them both. They might even have revelled in such an undertaking. And it wasn’t that strange an occurrence back then, a common way of covering up embarrassments.’

‘I’ve heard about such cases. It still happens today.’

The longer the interview went on, the more Fairfax settled into it, the more he spoke, and the more questions he asked. Hobbes watched his progress, hoping he kept on the necessary track.

Camilla continued, ‘Nicholas left home to fight in the war. After VE Day, he found a place of his own, in Bayswater. And Rosamund got married in 1943. Can you imagine, a mother leaving her child like that, without a thought in her mind?’

‘So then it was just you and Adeline?’

‘Yes. Auntie and niece. Sister and sister.’

Fairfax lit a cigarette. ‘Let me guess, if I can … Adeline found out the truth? About her real parents?’

Camilla frowned at this. And she started to pace about the room.

‘Who told her? You?’

‘No. No, our nanny did. Mrs Braithwaite. It was one of the last things she did, before she retired. I don’t know why she did it, perhaps out of some kind of guilt. But there it is.’

‘How old was Adeline when this happened?’

‘She was fifteen.’ Camilla frowned suddenly. ‘I was twenty-five. Can you imagine? Still living at home, looking after my sister who wasn’t really my sister. It doesn’t bear thinking about, looking back.’