I have a bird named Kyo who I bought a few days ago. He is well behaved and loves to sit on top of my head. I just noticed that he is missing feathers around his vent. He also has a pasty vent and I don't know how to clean it. He gets along with all my other birds and follows them around outside of the cage. But when I put him beside me when I'm working he puffs up. Is it normal? Also he sneezed a couple of times today.