New to the forum, my boyfriend has had chickens at his place for 10+ years and has never experienced this so I am hoping someone can give us some advice! We have 2 RIR hens and recently added 2 silkies, they are around 6 months old so they are still seperated from the other two... We noticed a month or so ago that our black silkie Dalhia had missing feathers on her head, it was a small spot and we just assumed it was the other roo silkie trying to peck at her, but we rehomed him a week ago and her head keeps loosing feathers, and there is a yellow crust on her head and face. Her appetite and personality seem normal, but I am freaking out now that I know for sure its not the other silkie...I don't see her loosing feathers or have the crust anywhere else but I don't know, so hopefully someone can help out, I also contacted the woman who sold them to us... I attached photos, we are in Los Angeles, CA. Thanks!!