firstly i dont know where he stands if his parents are not nationals,also although his not too old,he is if you know what i mean...he would have no problem joining for his age but he would be expected to excel,and be beasted around by guys a lot younger than him. I was in regt and there were not a lot of non nationals in there then,only those on detachment from foreign forces.I dont think being from the commonwealth gives you any more rights than any other country in the world when it comes to joining,the commonwealth is a trade issue not a citizenship issue,these days.