Should someone who lost their brother in the war repay bonus money after separating from the military?

I dont think he should have to repay it. I lost my twin brother in Iraq in July. I didnt know you could get out of military because of it though. I thought you could only do it in peace time? I know this is supposed to be an answer and not a question but if you know more could you email me. Im not in Iraq but I am serving in Korea. I dont know if I want out but sometimes I feel like I should but would like to know how if I decide to.