Who was Ratanji and what was the main source of his unhappiness despite his wealth?

According to Chapter 14, Ratanji was a very religious, popular, and wealthy Parsi merchant from Nizam's state. He possessed vast properties, including carriages, horses, and farms, and was known for his generosity. Despite his outward appearance of swimming in an "ocean of joy," he was deeply unhappy. The source of his constant worry was that he had no son to carry on his lineage, which made his immense wealth feel "entirely fruitless." He had twelve daughters, but the absence of a son left his mind without peace and filled him with daily contemplation and sadness.