Face reveal.

~ 3 days before the current date.

Average day. Before heading to the Court for the daily reunion, he makes a stop by the headquarters of Imperial Assassins to receive reports on the recent happenings.
He would have never expected what was about to come.
One of the officers tells him about a Nobody's-Child* who got involved in a case, deliberately causing a ruckus to help a suspect escape. That wouldn't be a big deal, something he'd not even need to know, but the officer tells him he was just about to contact him. And insists that he has to go to see this boy with his own eyes.

Sao knows that his men wouldn't risk to bother him for no reason, least of all an officer and veteran of his organisation. He agrees to see this person, curious about what's the matter.
They head downstairs, to the little dungeon of the building, and approach one of the small, there cells on the left.
A boy is chained to the bars, wearing the typical black robe Nobody's-Children are usually seen with.
As the General takes a better look at the face of the young man, he is left shocked to realise that he looks absolutely identical to WuXin.

He knows that WuXin had a twin, at birth, but like everyone else, he thought their oldest brother Zhao had killed him, as their abeoji ordered him to do. If it had not been for that fact, he could have as well taken it for a case or some creature playing tricks.
Sao tries to speak with the boy, but he doesn't know anything, not even his real name. Before he could make conclusions, the IA officer who led him there hands him the few belongings that they found on that guy, when they arrested him.

Among those items is a letter, that got opened, with the seal on it, broken. He reads what's written in it and shuts his eyes. The seal both outside and inside the letter is the undeniable proof that the document is authentic and in truth, Sao isn't even too surprised. It's very Zhao.
Not really having the heart to kill that boy - everything about WuXin makes him uncommonly sensitive - to just get rid of him and make things easier, he is forced to take him home with him, but not to the same residence where he is living with SangPil and family.

Sao chooses a more remote manor, where there won't be indiscreet eyes to make rumors to see 'WuXin' in such a poor state.
There, he explains WuNing about the letter, their family, WuXin and all the basic things he needs to know.
He also leaves him to the care of the servants to clean him up and give him a decent look. Not having many options in that moment, the servants give WuNing one of WuXin's hanfus to wear.

Before letting the new brother meet anyone, Sao tries to make sure he learns at least the most minimum manners and customs, to avoid making the whole family ashamed.
He secretly hopes that WuXin will kill him, when they will meet, but he knows that it probably won't happen.

*Nobody's Children are boys born from prostitutes in brothels, from unknown fathers. Zhao left WuNing to their care, thinking that he would be the safest among them. They are like a brotherhood, living in the street on thievery and little crimes, to survive together.