I have 4 birds and I love each and every one of them. I got the 4th bird, a GCC, in July, a present from my wonderful hubby for our 25th anniversary. I love this little guy bunches, but I will admit he has thrown my routine with the birds way out of whack. My other guys (a YNA, Blue Crown Conure and Senegal) are quite content to play on their playstands or on top of their cages, and though they don't physically interact with each other, they do co exist peacefully together during out of cage time. Those 3 have only just become flighted, but seem to prefer hanging out, foraging and destroying their toys. The little GCC, on the other hand, is too big for his britches. He thinks he's a big bird, is very curious and has no fear. He came fully flighted and he doesn't like hanging out on my shoulder or on his cage or playstand. He insists on constantly flying to or at the other birds and causes quite the ruckus. I now have to keep him caged when the other guys are out because I am afraid that someday I won't be fast enough and he'll end up getting hurt by one or more of the bigger guys. I try to give him one on one time, but because he is flighted I end up having to chase him down. I'm considering clipping him, so he will stay put for training sessions, but I keep putting it off. If I do clip him, I hope to only keep him clipped temporarily until I am comfortable with his training. Adding another bird (or two, or three) to the mix you already have will definately change the dynamics of the flock you have, it will change your routine, and for a time, there might be jealousy issues. To help with jealousy issues, I don't shower tons of attention on the new guy. He's last on the totem pole. He's the last to be let out and the first to be put back up. He's also the last to get his food, water and treats, showers, new toys, etc. We have a sort of pecking order with my flock and so far it has worked. I will admit that I give the amazon more one on one time, but I justify it because he is more of a difficult bird than the others. If I don't continually give him hands on time, he gets very demanding, territorial and bitey. And when his hormones are raging, it's pretty much hands off for that duration, so I guess I also try to make up for lost time. Good luck with whatever decision you make. It will change things, but that's not always a bad thing.