Introduction to the Twenty-Four Filial Sons Picture: Filial piety is the first among all virtues. Filial piety is one of the important ethical thoughts in ancient China. In traditional wood carvings, brick carvings and embroidery, patterns inscribed by the Twenty-Four Filial Sons are common. To show its characteristics, the farm has specially built a stalactite cave for the twenty-four filial sons, with pictures of the twenty-four filial sons hanging inside.