Aethra in Wikipedia
In Greek mythology, Aethra or Aithra (Ancient Greek: Αἴθρα,
the "bright sky"[1]) was a name applied to three individuals:
Æthra was a daughter of King Pittheus of Troezen and, with the
king Aegeus of Athens - or in some versions, Poseidon -father
of Theseus. Ægeus went to Troezen, a city southwest of Athens
that had as its patrons Athena and Poseidon, where Pittheus
got Ægeus drunk on unmixed wine and put him to bed with his
daughter. Following the instructions of Athena in a dream, she
left the sleeping Ægeus and waded across to the island of
Sphairia that lay close to Troezen's shore. There she poured a
libation to Sphairos, Pelops' charioteer, and was possessed by
Poseidon in the night. When she was thus doubly pregnant,
Ægeus decided to go back to Athens. Before leaving, he covered
his sandals, shield and sword under a huge rock, that served
as a primitive altar to Strong Zeus, and told her that when
their son would grow up, he should move the rock and bring his
weapons back. Aethra did as she was told, and Theseus,
recovering the weapons that were his birthright, grew to be a
great hero, killing the Minotaur, among other adventures...
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