Conflict in the army, what should I do?

I am French, but I am in the military, recently stationed abroad. I am married to a sister of our military commander (whose name I can't tell), and we have one child, son Baldwin. I have a stepson, too, and he is our commander's nephew, and he is here in the army with me. I haven't seen my son, my wife and my property for a very long time, and at last, we were to go home. But just before the departure, a local military leader Marsile asked for a meeting, to discuss a possible truce and such matters. So, we had to decide who to send there to talk to him. I was astonished when I saw my stepson jumping on his seat, waving his hand, because I knew that he was not usually very eager to participate in dangerous missions. He'd rather gad around our base and get drunk. Imagine what I felt, when my stepson nominated me! As our military commander (my brother-in-law and an uncle to my stepson) agreed, I must go. I think that my stepson nominated me on purpose, he hopes that I will be killed and he will inherit my property. I openly told him how I hated him for this, and he just laughed! He knows that he is invincible, he sucks up to his uncle and receives all the honours and promotions possible, without doing anything. I hate him, I hate his sidekick Olivier, who, in his turn, sucks up to my stepson to get promotions. But, of course, I must follow the orders. Yet, I can't think about nothing else but the trick my nephew played on me, so what should I do?