You might have cited the following examples highlighting Ismene’s hesitation to break the law:
At the beginning of the play, Ismene attempts to persuade Antigone against disobeying Creon by burying Polyneices; she thinks they are “weak women” who cannot stand up to men by challenging a “monarch’s will.”
Ismene believes that she and her sister “must obey” Creon’s commands or endure “worse” repercussions, and she pleads with her deceased brothers to “pardon” her.
As a matter of duty, Ismene chooses to “obey” the earthly authority and considers it “foolishness” to “overstep” her boundaries by opposing the king’s civil regulations. She states she lacks the capacity to question the state or infringe upon its “ordinance.”
You might have mentioned these points illustrating Ismene’s focus on secrecy:
After failing to sway Antigone from providing Polyneices with a dignified burial, Ismene urges her sibling to keep the matter “close and secret” and not disclose her “intent” to any man.
It’s noteworthy that Ismene's final scene in the play is significant. She is not seen again after Creon condemns her and Antigone to death. Although Antigone urges her to escape and choose life, Sophocles leaves Ismene's fate unresolved at the play's conclusion. One reason for this might be that she serves as a contrast to Antigone, rendering her fate less pivotal than Antigone's. Another possibility is that Ismene might have evaded capture and lived out her days quietly, as she has consistently valued silence.
You may have included some of these instances demonstrating Ismene’s steadfastness in not forsaking Antigone:
When Creon’s guards apprehend Antigone and present her to him, Ismene is unwilling to let her sister bear the entire blame. She asserts that she also “did the deed” of interring Polyneices and wishes to “share the guilt with her sister.”
As Antigone objects, Ismene requests that she not “scorn” her and permits her to partake in Antigone’s “work of piety.” Ismene desires to perish alongside Antigone, believing that life would hold no “profit” for her if she were to be “bereft” of Antigone.
Ismene also makes an effort to persuade Creon not to “slay” his “own son’s betrothed.” Sadly, her attempt to convince Creon to spare Antigone’s life does not succeed.
