Will, if he is pasionate about it and you are already taking him flying then you probably won't be able to stop him!
You are right there is a lot of twitter and bisted in the aviation industry, but if you come into it with a sense of adventure and your eyes wide open to the difficulties he (and you and your wife as his parents) will face, in particular that first job (oh and the cash involved), then you stand a chance of getting what you want out of it. A lot of people fall by the wayside for various reasons, but a lot of the time they are their own worst enemies, due to an expectation about the job that just wasn't real. Research it as much as you can with your son, just remember that the coveted airline position is not the be all and end all of aviation, there are a lot of alternatives. The airlines are usually the ones that pay the best, although you have to be prepared to give up your pound of flesh these days! But if you are considering coming in to the industry for the money then you might want to rethink your son's choice of career. Scroggs is definitely pointing in the right direction, see if your son can decide where he wants to go and also end up (long haul/short haul, airline/charter/biz jet/instructing/air taxi, Europe/Africa, the list is endless) and try and talk to as many people in that part of the industry as you can and see how they got their start. You will be amazed at how many people will be willing to help, if they can. Good luck!