During the Xuande reign, Liu De and his wife, who were over sixty and childless, ran a small inn in Hexiwu Town, Tianjin, by the Grand Canal. One snowy winter day, an old soldier named Fang Yong, accompanied by his twelve-year-old son Fang Shen, sought shelter at their inn while on their journey back to their hometown in Shandong. Liu De, showing no disdain for their poverty, treated them to wine and meat, and even invited them to stay the night, declaring, "Within the four seas, all men are brothers."

Fang Yong caught a severe cold that night. Mr. and Mrs. Liu promptly brought him soup and extra blankets. Early the next morning, Mr. Liu braved the snow to fetch a doctor. By then, Fang Yong was unconscious. After examining him, the doctor sadly announced, "This is 'double cold damage' (双感伤寒), an incurable disease, and he has only seven days left."

The Liu couple immediately closed their business to devote all their time to caring for Fang Yong. A few days later, Fang Yong passed away. The Lius buried him in their own ancestral cemetery. They adopted the now-orphaned Fang Shen, renaming him Liu Fang.

Liu Fang diligently helped with the family business and served his adoptive parents with great filial piety, leading to the gradual prosperity of their household. Everyone said this was the result of their virtuous deeds.

Years later, when his adoptive parents both fell ill, Liu Fang nursed them day and night without rest. After they passed away, Liu Fang buried them. He then returned to Shandong to move his birth mother's tomb, burying her alongside his adoptive parents. He continued to live a peaceful life running the inn.