I have a female Blue Front Amazon and a male Rosebreasted Cockatoo. I wouldn't call them buddies but they happily ignore one another and are safe out in the same room at the same time (on top of their cages, on play gyms, or at the table with us). I have an 10' diameter outdoor aviary on my back porch, and I can put the two of them in it together (duplicate food and water bowls on opposites sides of the unit) on a nice days with zero problems. They seem to enjoy the proximity of the other without getting in their own personal space. My Grey is a totally different story, though. My female Amazon HATES (and I do me LOATHES) my male Grey (DNA'd TWICE because I thought there HAD to be a reason for her to dislike him that much). She will divebomb him if he's out of his cage in the same room with her, and she will also bite a human that walks too close to the Grey's cage, just as a displaced aggression type thing. I've never seen a bird hate another one with such a dedicated passion. So, I'm not sure it has anything to do with the TYPE of parrot but is probably more related to individual personalities. Good luck with yours!