MMA RAMOTSWE and Mr. Polopetsi spoke to Sister Batshegi again, along with two other nurses, in Tati Monyena’s office. He had left them alone, as he had promised, but through the window they saw him hovering around anxiously in the courtyard outside, looking at his watch and fiddling with a line of pens that he had clipped in his shirt pocket. Sister Batshegi said little more than she had said in the ward, and the other two nurses, both of whom had been on duty at the time of the incidents, seemed very unwilling to say much at all. The deaths had been a surprise, they said, but they often lost very ill patients. Neither had been nearby at the time, they said, although they were quick to point out that they were both keeping a close watch on the patients involved. “If anything had happened, we would have known it,” said one of the nurses. “It is not our fault, you see, Mma. It is just not our fault.”

It did not take long to interview them, and then Mma Ramotswe and Mr. Polopetsi were alone in the office before Tati Monyena came back.

“Those nurses were scared about something,” said Mr. Polopetsi. “Did you see the way they looked? Did you hear it in their voices?”

Mma Ramotswe had to agree. “But what are they scared of?” she asked.

Mr. Polopetsi thought for a moment. “They are scared of some person,” he said. “Some unknown person is frightening them.”

“Sister Batshegi?”

“No. Not her.”

“Then who else is there? Tati Monyena?”

Mr. Polopetsi did not think this likely. “I think that he is somebody who would protect his staff rather than punish them,” he said. “Tati Monyena is a kind man.”

“Well, I don’t know what to think,” said Mma Ramotswe. “But it’s time for us to leave anyway. I don’t think that there is anything more we can do here.”

They drove back to Gaborone. They spoke to each other on the journey, but not about the visit to the hospital, as neither had much to say about that. Mr. Polopetsi told Mma Ramotswe about one of his sons, who was turning out to be very good at mental arithmetic. “He is like a calculator,” he said. “He is already doing calculations that I cannot do, and he is only eight.”

“You must be very proud of him,” said Mma Ramotswe.

Mr. Polopetsi beamed with pleasure. “I am, Mma,” he said. “He is the most precious thing I have in this world.” He seemed about to say something else, but stopped. He looked at Mma Ramotswe hesitantly, and she knew that he was about to make a request. It will be for money, she thought. There will be school fees to be paid, or shoes to be bought for this boy, or even a blanket; children needed all these things, all the time.