What advice did Das Ganu give to the merchant Ratanji, and why?

In Chapter 14, the Parsi merchant Ratanji, who was always sad because he had no son, confided in Das Ganu, in whom he had great faith. Seeing his distress, Das Ganu provided clear and direct advice. He told Ratanji, "Go to Shirdi; you will obtain your heart's desire." Das Ganu's counsel was for Ratanji to seek Sai Baba's darshan, bow at His feet, and explain the entirety of his secret sorrow. He gave this advice with immense confidence in Baba's divine power, assuring Ratanji that Baba's "handiwork is inconceivable" and that by surrendering to Him alone, his wish would be fulfilled. This suggestion appealed to Ratanji and set him on his journey to meet Sai Baba.