Basic training brings mental health issues out, but I'd think it's pretty painful to have that happen.

There was a girl in my basic training flight that had a sort of paranoid delusional thing (I don't know what the accurate classification would be). I noticed something wrong, told the TI (training instructor) and got (predictably) yelled at because I was invading the sanctity of the TI eating area and interrupting breakfast. She listened though, and the girl got the proper care. She regained health and a few weeks later returned long enough to say goodbye.

I'd guess and potential problems would be noticed in that 'trial by fire', but there's a chance they wouldn't be and life could get pretty bad. It would have been tragic for the girl I knew if she hadn't managed to get out of that stress-induced state.

I'm glad your nephew didn't have to go through that.