Diogenes Laertius, book II Xenophon
In this battle Epaminondas also fell. On this occasion Xenophon is said to have been sacrificing, with a chaplet on his head, which he removed when his son's death was announced. But afterwards, upon learning that he had fallen gloriously, he replaced the chaplet on his head. 55. Some say that he did not even shed tears, but exclaimed, "I knew my son was mortal."