“That’s Zulu,” said Mma Ramotswe. “Or Ndebele, or Siswati—one of those Zulu languages.”

“Then I can speak to them,” said Fanwell. “My grandfather went to the mines over there. He learned Zulu and he taught me. I practised it with him a lot. I am very good at languages, Bomma. You may think I’m useless, but I know a lot of words.”

“Ask them their names then,” said Mma Potokwane. “And we don’t think you’re useless.”

Fanwell handed Zebra’s lead to Mma Ramotswe and crouched down beside the children. They watched him solemnly.

He uttered a few words slowly, holding the boy’s hand as he spoke. The effect was immediate, the girl reaching over and taking his free hand while the boy gripped tightly. The girl whispered something to him, and Fanwell nodded.

“She is asking for water,” he said. “She says that she will tell us their names once they have had water.”

Mma Potokwane went into the office and returned with a cup of water. She passed it to the girl, who drank half of it before giving it to the boy. He drained the cup and handed it back to Fanwell. This was followed by more whispering.

“She says that they are brother and sister,” said Fanwell. “She says that she is called Buhle. That means beautiful. And her brother is called…” He leaned forward and asked the girl. “Sfiso,” he said. “I don’t know what that means, but it is a name they use.”

Mma Potokwane asked him to find out where they were from. “And their parents,” she said. “Ask them where their parents are.”

Fanwell posed the questions. The boy remained silent, but the girl spoke freely.

“I cannot understand everything she says,” said Fanwell. “But she says that their parents are late. She says they have been late for months. She says they were very thin.”

Mma Potokwane caught Mma Ramotswe’s eye. That was the prevailing euphemism: the slim disease.

Fanwell continued his translation. “She said that they were brought to Botswana from Swaziland by an aunt and left here. She said there is nobody to look after them in Swaziland. The aunt has gone, she says.”

Mma Potokwane sighed. “Not an unusual story,” she said. “Nobody to look after children somewhere else—dump them in Botswana and then go home to wherever you come from.”

“That’s not fair on you,” said Mma Ramotswe.

“It’s even less fair on the children,” said Mma Potokwane. She sighed again. “A child is a child. We shall not turn them away.”

Mma Ramotswe looked at Zebra. “I shall take the dog back, Mma,” she said. “You cannot look after the whole world.”