Hemera Dies Primordial

In Greek mythology Hemera (Greek: Ἡμέρα) was the personification of day and one of the Protogenoi or primordial deities. She is the goddess of the daytime and, according to Hesiod, the daughter of Erebos and Nyx (the goddess of night). Hemera is remarked upon in Cicero's De Natura Deorum, where it is logically determined that Dies (Hemera) must be a god, if Uranus is a god. The poet Bacchylides states that Nyx and Khronos are the parents, but Hyginus in his preface to the Fabulae mentions Khaos as the mother/ father and Nyx as her sister.

She was the female counterpart of her brother and consort, Aether (Light), but neither of them figured actively in myth or cult. Hyginus lists their children as Ouranos, Gaia, and Thalassa (the primordial sea goddess), while Hesiod only lists Thalassa as their child.

[source: http://en.wikipedia.org/wiki/Hemera]