Based on the introduction to his story, what principle does Damu Anna's life illustrate about devotion to Sai?

The introduction to Damu Anna's story in Chapter 25 serves to illustrate a key principle about devotion to Sai Baba: once one-pointed faith is established, Sai actively wards off the misfortunes of that devotee. The chapter states that Sai grants His followers their desired objects and removes their suffering. Damu Anna's life is presented as a prime example of this. He was a wealthy man but was childless, which was a great sorrow for him. As a result of his unwavering devotion and Sai's blessings, he was granted sons. His story is introduced as a "novel story" that will show the listeners how the "Guru-Mother is an Ocean of Mercy," demonstrating Sai's readiness to protect and provide for those who are truly devoted.