You will be king one day Macbeth. But remember Banquo, your son will be king one day too.
Dear Wife, I am writing to tell you that I will one day be king. Please hold in your madness and don't tell anyone because if you do they will think that I will kill the king, however I don't want to. Also Banquo's son will also be king one day... hopefully before me so that he doesn't kill me to take the crown. From Macbeth