Can you tell me the story of how Sai Baba treated Amir Shakkar's rheumatism?

According to Chapter 22, when Amir Shakkar detailed his illness of rheumatism to Sai Baba and prayed for deliverance, Baba's remedy was a simple instruction: he should stay steadily in the Chavadi. This was despite the Chavadi being a dilapidated, damp, and uncomfortable place. The text explains that Baba's medicine was only His word, and Amir was to accept it with faith, ignoring the wind, rain, or dampness. Amir stayed in the Chavadi for nine months, and while the external conditions were contrary to healing, his internal faith in Baba's command was certain, and because of that, everything went well.