What is the primary narrative used in Chapter 34 to illustrate the power of Udi?

Chapter 34 of the Shri Sai Satcharitra details the story of a doctor from Malegaon whose nephew was afflicted with a severe and incurable bone-cyst, also known as Hadyavran. The chapter explains that despite the boy's uncle being a degree-holding doctor and consulting with other expert physicians and surgeons, all native and foreign treatments, including surgery, failed completely. As a last resort, the family heard of the great saint Sai Baba in Shirdi. They traveled to see him, and upon hearing their plea, Baba gave them Udi to smear on the wound, reassuring them that the child would be cured. This story serves as the chapter's main illustration of Udi's miraculous healing properties.