1. Polycaste was
Nestor and
Eurydice's daughter. (Note: there were many women named
Eurydice in Greek myth. This
Eurydice is not the same as
Orpheus's wife.)
Nestor appears in both
The Iliad and
The Odyssey; he was a king of Pylos.
Being
Nestor's daughter also made Polycaste the granddaughter of
Chloris (or, rather,
a Chloris, because there were several women with that name in Greek myth). She was one of seven sons and seven daughters of Niobe and Amphion, collectively known as the Niobids; her birth name was Meliboea.
The Niobids were all slaughtered for their mother's impiety to the gods, save for Meliboea. (In some versions, Meliboea doesn't survive the massacre, however.) Meliboea changed her name to
Chloris after the ordeal.
Niobe's foolishness was her boastfulness and pride. She bragged that though
Leto, mother of the twin deities
Apollo and
Artemis, had borne two gods, Niobe had given birth to
14 children. Therefore, Niobe reasoned, she was an even greater mother than
Leto. Needless to say,
Apollo and
Artemis were none to happy about this slight against their mother, and avenged her in the way the Olympian deities often performed revenge.
2. Polydora was borne by five separate women in myth. Among them were a daughter of
Antigone (in turn the daughter of
Oedipus and his mother
Jocasta), an Oceanid, and an Amazon.
I was lazy and didn't include the genealogies of those I didn't know off the top of my head. I had to look up the info above.
I took my (very long, but not nearly complete) list of mythological names from various sources, and haven't yet put in namesakes. I just have the names themselves listed for now.
Miranda