I have been in similar circs except we had no kids. I am betting that its tremendously exciting for your son and also a compliment to him, he is feeling no end of a fellow, and he has rushed home, poured it all out to his partner and hadn't really thought that she might not be similarly excited. I really think if you give your son any advice at all, the advice should be to draw breath and reassure his partner that she and the children come way before the job for him and always will. Even today I think that wives do bear the brunt of any move of this kind and they should both be looking into what would be in it for his family, what there would be for his partner to do, what life would be like and so on. When they move out there if they go, he will be off to work, the kids will be off to school, what will his partner do? Does she work here? If she wants to, could she work there?