The Rich Man Did Not Believe the Taoist's Words, and His Family Died of Hunger and Cold

During the Qing Dynasty, there was a man in Jiangyin who was illiterate but rich. However, he still had no son when he was over 40 years old. He later bought a concubine, who gave birth to a boy the following year. One day, a Taoist priest knocked on his door. Why did the Taoist priest come at this time?