We "ground" Kiwi when he starts getting excessively loud ( cover his cage for 10 minutes so he can calm down) and it's worked quite well. He doesn't really wake up the neighborhood the way he used to anymore, but it was easy door him to connect inappropriate screaming (which he only did in his cage) with the instant reaction of being covered. However, aggression tends to be a lot harder to deal with than other behavioral issues, especially when it's directed towards one person. I think it will be very difficult for your bird to make that connection that him attacking your brother is the reason he's getting put up. There's a good amount of time passing and emotions flying high between the attack and him being put up. I think a better approach for this issue would be your brother working with him more. Perhaps your brother could start doing some activities with him that he likes (such as feeding him or giving him a bath)? I think learning to tolerate your brother would make more sense to him than trying to connect an action a couple minutes ago with a "punishment" being delivered right now. And since instinct kicks in when were being attacked by an animal, it is probably safer for the bird to be clipped at the moment while your brother works on developing a better relationship. It would be a terrible thing for him to accidentally kill the bird because he was trying to get him off or moved the wrong way during the attack. It would be much safer for both of them not to have a aggressive flighted bird. Best of luck.
