The plays were written across thirty-six years of Sophocles' career and were not composed in chronological order, but instead were written in the order Antigone, Oedipus Rex, and Oedipus at Colonus. Nor were they composed as a trilogy – a group of plays to be performed together, but are the remaining parts of three different groups of plays. As a result, there are some inconsistencies: notably, Creon is the undisputed king at the end of Oedipus Rex and, in consultation with Apollo, single-handedly makes the decision to expel Oedipus from Thebes. Creon is also instructed to look after Oedipus' daughters Antigone and Ismene at the end of Oedipus Rex. By contrast, in the other plays there is some struggle with Oedipus' sons Eteocles and Polynices in regard to the succession. In Oedipus at Colonus, Sophocles attempts to work these inconsistencies into a coherent whole: Ismene explains that, in light of their tainted family lineage, her brothers were at first willing to cede the throne to Creon. Nevertheless, they eventually decided to take charge of the monarchy, with each brother disputing the other's right to succeed. In addition to being in a clearly more powerful position in Oedipus at Colonus, Eteocles and Polynices are also culpable: they consent (l. 429, Theodoridis, tr.) to their father's going to exile, which is one of his bitterest charges against them.