Wikipedia
In Greek mythology, Euryganeia (, Eurygáneia) is occasionally named as Oedipus' second wife and the mother of his children, Polynices, Eteocles, Ismene and Antigone. She was either a daughter of Hyperphas or Jocasta's sister. According to Pausanias, the statement at Odyssey 11.274—that that the gods soon made the incestuous marriage between Oedipus and his mother Jocasta known—is incompatible with her bearing four children to him. The geographer cites the Oedipodeia as evidence for the fact that Euryganeia was actually the mother of Oedipus' brood. Pherecydes, on the other hand, attributed two sons (named Phrastor and Laonytus) to the marriage of Jocasta and Oedipus, but agreed that the more famous foursome were the children of Euryganeia. There was a painting of her at Plataea in which she was depicted as mournful because of the strife between her children. Following Euryganeia's death, Oedipus married Astymedusa, who plotted against her stepsons.