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Oneiroi
In Greek mythology, the Oneiroi or Oneiri (, "Dreams") were, according to Hesiod, sons of Nyx (Night), and were the brothers of Hypnos (Sleep), Thanatos (Death), Geras (Old Age) and other beings, all produced via parthenogenesis Cicero follows this tradition, but describes the sons of Nyx as fathered by Erebus (Darkness).; according to Ovid they were the sons of Hypnos and his wife, Pasithea (therefore making them Nyx's and Erebus' grandsons).
Euripides calls them instead sons of Gaia (Earth) and pictures them as black-winged daemons.