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What happens to Antigone's and Ismene's brothers?

Answer:
That they kill each other in battle over the throne of Thebes is what happens to Polyneices and Eteocles, Antigone's and Ismene's two brothers.

Specifically, the twins inherit the throne when their father, Theban King Oedipus, is forced into exile for having - albeit unknowingly - killed his royal predecessor and own father, Theban King Laius. The twins are to alternate years of rule in a joint power-sharing arrangement. But Eteocles refuses to give up the throne and forces Polyneices into exile. Polyneices comes back with an army of invading Argives and disgruntled Thebans. The two brothers end up fighting and killing each other.
First answer by Ginezumi. Last edit by Ginezumi. Contributor trust: 903 [recommend contributor recommended]. Question popularity: 1 [recommend question].