No, that’s no use. You not only knew her but you knew her very well. Otherwise, you wouldn’t look so guilty about it.

Sheila says this to Gerald at the end of Act One, in regards to Eva/Daisy. Sheila realizes, as soon as the Inspector says the name “Daisy Renton,” that Gerald has known her, and known her intimately. She encourages Gerald to come clean to the Inspector, because Sheila understands at this point in the play that the Inspector seems to know everything about the family already. The Inspector is not so much inspecting the family as he is confirming what he already seems to know, and making sure that the family realizes the consequences of their actions.

Sheila points out that Gerald already “looks guilty.” This means that, on top hurting Sheila with his illicit relationship, Gerald also might feel some amount of guilt regarding his treatment of Eva/Daisy. It is revealed that Gerald was, largely, kind to Eva/Daisy, although he breaks off the relationship without much explanation, then returns to Sheila and says nothing of what has transpired. Gerald, like Sheila, is willing to eventually accept that he is complicit in the events leading to Eva/Daisy’ death. Though at first Gerald believes the Inspector’s “unofficial” status with the police department might make the events of the evening a total hoax, Gerald does admit to Sheila in Act Three that his confession to the affair in Act Two is genuine. He reiterates that he realizes the consequences of having an affair, even if Eva/Daisy did not actually commit suicide. Sheila’s relationship with Gerald is perhaps the most functional and honest in the play. It is an example of what happens when two people speak to each other about their misdeeds, and then attempt afterward to reconcile. At the end of the play, Sheila and Gerald leave open the possibility that they might reunite as a couple, even after what they have learned about each other.