Half of you will not believe, others will want me to admit to Briarcliff. But I have proof that the Constance's fourth son is actually:
The Albino who appeared in that infamous fake image that ran this wiki for a long time.
Visiting a Brazilian site (#nationpride) I bumped into a report (Albino ), it says that the actor, Stephen Thompson, came to be hired as a supporting actor, but was cut from the series. He even had a scene with Evan Peters in the Pilot episode (pictures below), but this scene is not shown on the DVD / Blu-Ray of the first season.