We have four 2 month old Brahma chickens and this one demonstrated very different behavior from day 3. Always "herding" the others, making sure they are all at certain place, jumping, pecking, complaining if the other chickens are held. Also 20-30% bigger than the others. The other three are very calm and approachable. We now have them together with our only adult Orpington. The transition went very smooth for all of them but it seems this Brahma is starting to question the Orpington dominance. At what age does rooster start to challenge the top hen? (We cannot have roosters and would have to rehome anyway). I am fairly new to the chickens so wondering if this is could be normal hen's behavior.