Hm.. I can't tell. I'd think it to be a bit unofficial as in old Rome: every wedded man had his play-boy, but had his "duties" in raising a family as well. Say, an arranged marriage for them to have children and apart from that no ties whatsoever. I can't decide over that as this isn't my roleplay, but that would seem most logical to me, as purebloods are not at all about stopping the bloodline.