Ryuuken. He is born of your seed. There is no denying the connection.
When this feeling wakes you from your sleep, you are already up and dressing without thinking. It might be the invasion that you all have been waiting for. It might not. This wider picture is gone from your view in the focus caused by a father's terror that his son might die.
You knew he went to Sereitei the first time, with that shinigami boy. It is your business to know what he is up to, after all. The question that haunts you still, though, when your mind drifts, is why did you let him go? You knew what might happen. You knew what your father had given him, bypassing you in the inheritance. You knew.
But some small feeling in your heart kept you back.
You rationalized that it was just to teach him a lesson. You tell yourself that, but really you know that you truely just want him to /live/.