The reality of birth-and-death is such that the sorrow of parting is mutually felt by all generations. A father cries over the death of his children; children cry over the death of their father. Brothers, sisters, husbands and wives mourn each other's death. According to the basic law of impermanence, whether death will occur in order of seniority or in the reverse is unpredictable. All things must pass. Nothing stays forever. Few believe this, even if someone teaches and exhorts them. And so the stream of birth-and-death continues everlastingly.
Buddha Shakyamuni, in The Sutra on the Buddha of Infinite Life (the Larger Pure Land Sutra), published in Three Pure Land Sutras, p. 286.