The Master said, "The years of parents may by no means not be kept in the memory, as an occasion at once for joy and for fear."
子曰、父母之年、不可不知也、一則以喜、一則以懼。
Analects 4.21
The same idea in other traditions
Hearken unto thy father that begot thee, And despise not thy mother when she is old.
Caring for mother and father, kindness to children and partners, and unstressful work: this is the highest blessing.
But if any widow have children or nephews, let them learn first to shew piety at home, and to requite their parents: for that is good and acceptable before God.
When thy servant becomes stricken in years, be not unmindful of thy obligations towards him. If old age binds his hand from service, the hand of generosity yet remains to thee.
This is the road to it: to serve the Gurus and the old (teachers), to avoid throughout foolish people, to apply oneself earnestly to study, and to ponder zealously on the meaning of the Sûtras.
And We have enjoined on man (to be good) to his parents: in travail upon travail did his mother bear him, and in years twain was his weaning: (hear the command), "Show gratitude to Me and to thy parents: to Me is (thy final) Goal.
When the Great Tao (Way or Method) ceased to be observed, benevolence and righteousness came into vogue. (Then) appeared wisdom and shrewdness, and there ensued great hypocrisy. When harmony no longer prevailed throughout the six kinships, filial sons found their manifestation; when the states and clans fell into disorder, loyal ministers appeared.