What are the thoughts about filial piety and giving back to birds in virtue poems?

The second dock cries at night in the Tang Dynasty: Bai Juyi lost his mother in the second dock, and he was speechless. Don't fly day and night, keep the old forest old. Crying in the middle of the night every night, everyone who smells it will be moved. If you tell me in your voice, you won't give back to your heart. A hundred birds have no mother, but they are very sad. What makes you sad should be your mother's kindness. Once upon a time, there was a Wu Qizhe whose mother died. What disciple, the heart is not as good as a bird. The second thing gives the second thing, and the bird once applied.

The lamb kneels for milk and the crow feeds back, which is the foundation of being a man and honoring parents. The grace of a drop of water, the gratitude of Yongquan, the resentment of forgetting the time, the short time to complain, the long time to be grateful, and the sorrow for parents. I don't know if my parents are passionate about jade, but I know the horsepower in the distance. I have long heard of people's hearts, and God has pity on grass. The world is heavy and sunny.

Filial piety of all virtues is considered as a kind of filial piety. Secondary dock is a small crow with filial piety, so it is called secondary dock. Tang's poem "The Nightingale in the Second Dock" said: The second dock lost its mother, and it was dumb and mourned. Don't fly day and night, keep the old forest old. Crying in the middle of the night every night, everyone who smells it will be moved. If you tell me in your voice, you won't give back to your heart.