What prompted the parents of the sick child to travel to Shirdi, and what was their plea to Sai Baba?

As narrated in Chapter 34, the parents of the child suffering from a bone-cyst were desperate after all medical remedies and even worship of their family gods had failed. They heard word of a famous Avaliya (saint) in Shirdi, Sai Maharaj, who could heal incurable diseases with his Udi. Motivated by this last resort, they decided to try this final remedy, believing there was nothing to lose. Upon reaching Shirdi, they prostrated at Baba's feet and, with pitiful faces and choked voices, narrated their son's suffering. They pleaded with Sai Samarth to place his hand of protection on the child and remove the ailment, having come seeking refuge with total devotion.