Mma Ramotswe gasped. Mma Potokwani, who had stopped looking at the ceiling, was staring incredulously at the housemother.

‘His sister,’ muttered Mma Ramotswe.

‘It was very shameful,’ said Mmamodise. She frowned. ‘But you knew this, Mma. This lawyer you mentioned knows all this?’

‘We suspected something,’ said Mma Ramotswe. ‘I did not expect that.’

Mmamodise turned away. Her voice was trembling. ‘I am very ashamed of myself. I thought you knew. Now I have told you something that should be kept very secret, Mma. I have spoiled that.’

‘No, Mma,’ said Mma Ramotswe. ‘You did not do that deliberately. And I promise you, I shall not speak of this to anybody.’ She turned to Mma Potokwani. ‘And you will say the same, won’t you, Mma Potokwani?’

Mma Potokwani nodded. ‘I shall not speak of this either.’

Mmamodise seemed reassured. ‘It was a terrible thing. I know about it because I was there when it happened. I was in the house and I heard the voices and all the crying. The old man was still alive and he said that this would kill him. I think it made his death come earlier.’

‘Does the boy know?’ asked Mma Ramotswe.

‘He does not know. He thinks that his father is a man who worked on the farm and then left.’

There was another question for Mma Ramotswe to ask. ‘And Rra Edgar? He knew?’

Mmamodise shook her head. She spoke with some embarrassment now and Mma Ramotswe understood; people like Mmamodise did not like talking about such matters. And she would not press her. Why should people not have their realms of privacy and reticence?

‘When it happened, the old man did not want his son Edgar to know that he was becoming a father. It was too shameful. You see, Mma, what I heard was this: the girl confessed to her father that she had shared a blanket with the brother just once. That was all. I don’t think that Rra Edgar ever knew that the consequence of what he had done was the sister’s pregnancy. You see, Mma, I don’t think any of them could face it.’

Mma Ramotswe nodded. She noticed that Mmamodise had used the old-fashioned expression – to share a blanket. It was how people spoke of these things.

‘I see,’ she said. She knew now. It was shame, and an understandable shame at that.

They sat in silence for a while; nobody seemed to want to say anything. The disclosure had been so powerful that Mma Ramotswe and Mma Potokwani were shocked into speechlessness. And for her part, Mmamodise was wrestling with guilt over having revealed the painful secret. Mma Ramotswe could tell that, and she reached over and touched the housemother on the arm.