why do you think ann decided not to say anything about joe? base your answer on what you already know about ann.

Ann doesn't want to destroy anyone else's life and she is loyal to the man she loves. The only thing Ann wants in act three is to marry the man she loves and to have his family face the truth about Larry.

I think that Ann has decided not to do anything about Joe in act 3 because like Chris she has high moral values and she knows that whatever she will do - the dead pilots can't return to life. Also, she doesn't want to ruin the families completely, the most important thing to her right now is to marry Chris, and she doesn't want to hurt him.