Xiao is the respect and devotion owed to parents, living and dead. The Analects calls it the root of humaneness. It extends to ancestral rites and, by analogy, to loyalty in society. The Classic of Filial Piety made it a cornerstone of Chinese ethics.
Xiao
Filial piety: reverence and care for parents and ancestors, the root of virtue in Confucianism.
Also: hsiao, filial piety