The text mentions Damu Anna had a personal problem that was resolved. What was it, and how was it fixed?

The narrative in Chapter 25 explains that Damu Anna, despite having two wives, had no children. This was a significant personal issue for him. The text states that this problem was resolved after he received Sai Baba's blessings, which led to him being blessed with sons. This event is presented as a direct result of Sai's grace and is mentioned in the context of Damu Anna's unwavering devotion, which included his vow regarding the Ram Navami festival flag.