What is the primary analogy used in Chapter 15 to describe how Sai grants his vision to devotees?

Chapter 15 explains the dynamic of how Sai grants his vision to loving devotees through the analogy of a mother cat and her kittens. The text describes how the kittens will run to their mother with love, and even if she initially growls, their persistent affection causes her to relent. As detailed in Chapter 15, the mother cat then forgets her growling, spreads herself on the ground, and allows milk to flow with affection. This illustrates how a devotee's unwavering love and persistence can earn the grace of the Guru, who, like the mother cat, responds to sincere devotion by bestowing blessings.