Itylus

In Greek mythology, Itylus, or Itylos, was the son of Aedon and King Zethus of Thebes. The mythic theme was an ancient one, for Homer's listeners were expected to know the allusion, when Penelope reveals to the still- disguised Odysseus her anguish of a night: "I lie on my bed, and the sharp anxieties swarming thick and fast on my beating heart torment my sorrowing self. As when Pandareos' daughter, the greenwood nightingale perching in the deep of the forest foliage sings out her lovely sing when springtime is just begun, she varying the mainfold strains of her voice, pours out the melody mourning Itylos, son of the lord Zethos, her own beloved child, whom she once killed with the bronze, when the madness was upon her; So my mind is divided, and starts one way, then another" (Odyssey xix.519-24; Richard Lattimore's translation). As one of only nine similes in the Odyssey that are longer than five lines, the thematic complexity of the image and its multiple points of contact with Penelope's situation has arrested the attention of many readers. Aedon accidentally killed Itylus "in her madness" and was stricken with grief and guilt. In pity, the gods turned her into a nightingale, which cries with sadness every night. In an explanatory scholium on this passage, an anonymous scholiast, echoed by Eustathius, explains that Aedon attempted to kill the son of her sister-in-law and rival, Niobe, but accidentally killed her own son instead: thus, the gods changed her into a nightingale to weep for eternity. The setting of the episode is Thebes.
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[Greek heroic] The son of Zethus and Aëdon, who was accidentily killed by his mother.