Du Mu A poignant scene in "Qingming", what kind of story is hidden?

Qingming Festival is one of the traditional Chinese festivals and an important festival to worship ancestors. There are many theories about the origin of the Qingming Festival, one of which is derived from Jie Zitui of the Jin State in the Spring and Autumn Period, in order to be loyal to the Duke of Jin Wen, he set fire to himself, and in order to commemorate him, he forbade making a fire on the third day after his death and only ate cold food, which is the origin of the Cold Food Festival. Later, the Cold Food Festival and the Qingming Festival merged to become one festival.