There are two major conflicting stories for Aphrodite's origins: Hesiod (Theogony) claims that she was "born" from the foam of the sea after Cronus castrated Uranus, thus making her Uranus' daughter; but Homer (Iliad, book V) has Aphrodite as daughter of Zeus and Dione. According to Plato (Symposium 180e), the two were entirely separate entities: Aphrodite Ourania and Aphrodite Pandemos.
Various Greek myths account for Scylla's origins and fate. According to some such as Eustathius, she was one of the children of Phorcys and Ceto. Other sources, including Stesichorus, cite her parents as Triton and Lamia. Hyginus says Scylla was the daughter of the river god Crataeis.
Most sources describe Medusa as the daughter of Phorcys and Ceto, though the author Hyginus (Fabulae Preface) makes Medusa the daughter of Gorgon and Ceto.