I think we can be fairly confident (in most cases), that parents willing to go through such an intense procedure for the love of their child, will also have equal love for the any proceeding children they might have. I think perhaps the rights of the "donor" child here are seriously called into question though, the new child of course has no voice in this matter. This procedure which defies natural selection, is highly controversial for good reason. I suppose it will be some years before we can calculate the full emotional and physical costs of such a decision. As for this new "technology" not being used for Social engineering purposes, well it's impossible to stop it now, the cat is out of the bag, and it will only be a matter of time.
...as one of my lecturers said yesterday "if someone's trying to ban it, you can guarantee someone's doing it"