When I went to RTC for Navy a year ago, I was allowed to make a 5min call, we had to use paycards and mine didn't work. I was so mad because the thing didn't work and It took me another month before I was able to call home, just to find out my cousin was killed and the funeral was a few days before.
I was never lied to by my recruiter and I stay in contact with him, but when I first went to MEPS I wanted to be a SeaBee but the lady said the job was full, but instead of pulling the "Oh I'm not joining then card" I said oooo Hospital Corpsman, give me that! Even though it wasn't my first choice I'm glad I became a Corpsman. I work with a few Marines at my command and a few of them talk about boot and things that happened there but they said in the end, its made them a better person, and they think twice before they do something that could ruin their career or life. Your Brother-In-Law will be fine and let me tell you from my experience in boot camp, letters of encouragement help the most. In each letter let him know its all a game to get the weakest out and the weaker, stronger.