With the character of Antigone, the reader of the Oedipus Trilogy might get a false impression of watching a young girl grow up, as in a novel or a true series of related plays. Remember that each play of the Oedipus Trilogy stands on its own. Although the stories of the three tragedies are connected, Sophocles did not write them in chronological order, nor did he mean for them to be viewed in a particular sequence.
At the conclusion of Oedipus the King, Antigone, with her sister Ismene, represents both the helpless innocence of a child and the undeniable proof of an incestuous union. The audience recognizes her pitiful, two-fold vulnerability, but beyond this she remains silent and unknown
In Oedipus at Colonus, Antigone epitomizes sacrifice and loyalty, caring for her blind, wandering father with no regard for her own needs or aspirations. Antigone's devotion to her father makes her an admirable character on her own, but also raises the audience's opinion of the sometimes cantankerous Oedipus, as a figure able to inspire and keep such love.
As the heroine of Antigone, Oedipus' daughter grapples with Fate on her own, not just as a child or a dutiful daughter. Her decisiveness and courage appear in stark contrast to Ismene's passive timidity, and, in this tragedy at least, overshadow even her brother Polynices' bold attempt to take Thebes. In championing the laws of the gods above the laws of the state, Antigone occupies the ultimate high moral ground, but she is not impervious to doubt. Just before she is led off to her death, Antigone mourns the life she is leaving by her own choice and even seems to regret her decision. The moment passes, however, and may represent simply a small proof of human weakness that makes Antigone's strength all the more dramatic.