One of my babies has started acting like a bully. I think he is a male, because his comb is much more pronounced than any of the others. I am not sure what he is, just bantam, and about 4 weeks old. He runs up to the other chicks, (3 others) and either jumps at them, making them squeak, or runs up to them and pecks at them. He mostly does this to the biggest chick who I assume is a fews days older than him, because of the feathering. I got them at Atwood's, and I know one is cochin, and one is silky, but the "bully" and the big one I don't know. They also are not the same breed as each other, Bully is featherfooted, and the other isn't. How can I nip this bullying in the bud? ps, culling is not an option.