What was the advice Swami Samarth gave to Ratanji to help him have a son?

The provided text from chapter 14 does not mention Swami Samarth offering any advice to Ratanji. The person who advised the wealthy Parsi merchant was Das Ganu, in whom Ratanji had great faith. Seeing Ratanji's distress over not having a son despite having twelve daughters, Das Ganu recommended a spiritual solution. As detailed in chapter 14, he told Ratanji, "Go to Shirdi; you will obtain your heart's desire." Ganu's counsel was for Ratanji to take Sai Baba's darshan, bow at His feet, and explain his situation, trusting in Baba's inconceivable power to find fulfillment.