My about 4 month old chicken is very active yesterday. However, today, my mom found him inside my chicken's cage, lying down and lethargic. He is a free range chicken, and since about 3 weeks ago, him and his siblings started to sleep on the branches of the mango tree. Probably it is at least 10 feet above the ground of the cage where they want to roost. Whenever he try to go inside the cage, other chickens will peck on him, so I think that he is pecked a lot when he is on the cage today. However, whenever I saw him on the ground inside the cage, he can easily run away from the aggressive chickens and get out of the cage. He get dry fowl pox and wet fowl pox, although, I think it is a mild case for both right now. I tried to take out some yellow cheesy looking substance in his mouth today. Interestingly, I saw the same thing, but significantly smaller near the opening of the trachea. I took it out, but he had no trouble breathing at all, even before I took out the wet fowl pox lesions. The way his legs looks when he is standing up looks normal, but he doesn't want to walk or run at all, and he doesn't want to eat or drink. Also, he is acting much worse, after I took out the wet fowl pox. He can no longer stand after I finish doing it, and his eyes are closed most of the time. I tried to take out the wet fowl pox moderate or severe lesions in my other 2 chickens, but they are active after I did it. Did he eat something bad for his health? Why does it look like, that he is dying?