Mma Potokwane guessed Mma Ramotswe’s thoughts. “It was perfectly all right,” she said. “Children are smaller. There’s always room for one or two more children.” She turned and clapped her hands. “Now, children, nobody is to go in the water. Play up here. Look, there used to be some swings over there. And a slide. So there’s lots to do.”

“Be careful of crocodiles,” warned Mma Ramotswe. “You don’t want to be eaten.”

A small boy with wide eyes looked up at Mma Ramotswe. “Would a crocodile eat me, Mma?” he asked politely. “Even me?”

Mma Ramotswe smiled. Even me. None of us thinks that we will be eaten; no child thinks that he will die. “Only if you weren’t careful,” she said. “Careful boys are never eaten by crocodiles. That is well known.” As she spoke, she realised that this was not true: that farmer had been careful. But children could not be told the unvarnished truth.

“I’ll be careful, Mma.”

“Good.”

Mma Potokwane had brought two of the housemothers with them, as well as a couple of volunteers from Maru-a-Pula School. The children flocked round the teenage volunteers while the housemothers set out the picnic on small trestle tables. Mma Potokwane and Mma Ramotswe found a small section of wall, shaded by a tree, and sat down on that.

Mma Potokwane drew a deep breath. “I am always happy when I am in the bush,” she said. “I think everybody is.”

“I certainly am,” said Mma Ramotswe. “I live in a town, but I do not think my heart lives there.”

“Our stomachs live in towns,” said Mma Potokwane, patting the front of her dress. “That is where the work is. Our stomachs know that. But our hearts are usually somewhere else.”

They were silent for a while. Above them, in the branches of the acacia, a small bird hopped from twig to twig. Mma Ramotswe watched the children exploring the abandoned playground. Two boys were kicking at the fallen swing posts, causing the dried mud of the termites’ activity to puff up in little clouds of dust.

She pointed to the boys. “Why do boys destroy things?”

Mma Potokwane sighed. “That is just what they do,” she said. “When I first started to work with children, years ago, I used to ask myself questions like that. But then I realised that there was no point. Boys are the way they are and girls are the way we are. You might as well ask why those dassies sit on the top of rocks. That’s just the way they are.”

It was true, thought Mma Ramotswe. She liked doing the things that she liked doing, and Mr. J.L.B. Matekoni was the same. She watched the children. “They seem very happy,” she said.