Board Thread:Speculation House/@comment-4830106-20140905003518/@comment-10390252-20140909144222

You're missing the key point - The details of a person whose name Yang does not know. If Yang's father and mother did not marry, there will be no marriage certificate. Given that she evidently had no interest in being Yang mother, she may have asked that her name not be recorded on the birth certificate. Without a name, a relatively few documents that have either been classified, modified or never completed fully would be enough for her to vanish for someone just looking for a face, not a name.

If, and this is very possible, that Powers That Be have a particular reason to want her to have vanished, then it gets even harder.

Yang has only just recently got to interrogating underworld information brokers so I think it is reasonable to assume that all normal options were exhausted and fruitless.