The terrible death of the two brothers Eteocles and Polynices did not, as you might suppose, end the siege of Thebes. No sooner were their funerals over, than both armies began to fight again; and they continued the contest until all the chiefs had been killed except Adrastus only.
Most of the soldiers had also been slain: so Adrastus made up his mind to go home, and wait until the sons of these fallen heroes were old enough to fight, before he went on with the war. As they thought it their duty to avenge all injuries, and especially the death of a relative, Adrastus had no trouble in getting these youths to march against Thebes. So they began a second siege, which was known as the War of the Epigoni, or descendants, because the young warriors took up their fathers’ quarrel.
Such was the bravery of these young men, that they succeeded where their fathers had failed, and after a long struggle took the city of Thebes. As Polynices was dead, and could not claim the scepter he had so longed to possess, they put his son Thersander upon the throne.
This young man ruled for a while in peace; but because his sons were insane, the Thebans thought that the gods still hated the race of Oedipus: so they drove these princes away, and chose another and less unlucky family to rule over them instead.
Even the daughters of Oedipus were very unhappy; for Antigone, having taken the part of her brother Polynices, was put to death, while her sister Ismene died of grief.
Such was the end of the race of Oedipus, a king who has been considered the most unhappy man that ever lived, because, although he meant to be good, he was forced by fate to commit the most horrible crimes.
From: H. A. Guerber, The Story of the Greeks; edited for this online publication, by ELLOPOS BLOG