Can you elaborate on the metaphor of the mother cat and her kittens as it is described in Chapter 15?

Certainly. In Chapter 15, the relationship between Sai and his devotees is compared to that of a mother cat and her young. The text describes how kittens, seeking nourishment, will lovingly run towards and cling to their mother upon her return. The mother might initially growl, causing a momentary pause, but the kittens persist and swarm her again. This loving persistence prompts the milk to flow, and the mother forgets her previous growling and settles down with affection. As detailed in Chapter 15, this illustrates that a devotee's persistent love and faith, even in the face of perceived indifference, will ultimately be rewarded with the Guru's grace and affection.