Based on the provided text, what does the story of Damu Anna teach about faith and devotion?

The story of Damu Anna, as introduced in Chapter 25, serves as a key lesson on the power of faith and devotion. The narrative begins by stating that when a devotee establishes 'one-pointed faith,' Sai wards off all their misfortunes and removes their suffering. Damu Anna is the living example of this principle. He was a wealthy bronze-smith from Ahmednagar, but his wealth couldn't solve his problem of being childless. His unwavering devotion, demonstrated by his long-standing vow for the Ram Navami flag, was rewarded when Sai blessed him with sons. This shows that sincere devotion and faith can attract divine grace to overcome even profound personal difficulties.