My son has a terminal illness and my husband just started Basic training what should I do?

my husband has been in Basic training for 2 weeks now. We found out my son has a disease that will shorten his life and causes him to be sick often. My husband has been allowed to call home to check up on him. His drill sgt. has been worried about my husband seeming upset alot. I am worried and don't know if they will do something like discharge him because my husband is having such a hard time dealing with being away from our very sick little boy. I don't know if my husband is depressed because when i talk to him on the phone he seems very upset and hard to understand, so i don't know what is going on. His drill sgt. is always there with him asking if everything is ok. Does anyone know what might happen or what they will do? I don't want my husband to get a dishonorable discharge.