These pictures are a little dark, and once again I missed the beginning of the confrontation as I really don't just sit with a camera poised to take pictures of the parrots all day long!
Thomas was reading the paper and Max and Rocky were walking around, probably desiring some attention. Of course, they'd both rather not have to share him. I'm not sure who started it, but there was some tail grabbing taking place, by both parrots. Since Rocky's tail is longer, Max is usually more successful.
I am inclined to mostly blame Rocky, while Thomas is inclined to mostly blame Max.
In any case, Rocky ran to Thomas for protection:
And Max continued after him -- whether to resume the altercation or seek protection of her own, I don't know. Thomas separated them and Max flew off.
A few weeks back, D. Richard asked if I thought that Max and Stella would ever get to the point of preening each other. I hope I am proven wrong, but I can't see that happening. Stella has been in the house three years this month (!) I think that Stella would like to preen and be preened by Max, but Max really wants nothing to do with it. Whenever Stella approaches her, Max walks away and puts her foot up as a sign to stay away. If Stella persists, Max flies off. Max never approaches Stella in a friendly manner.
Given their ages (Max is 9 and Stella is presumed to be around the same age), they should have a few more decades to live together, so maybe a preening type of friendship will form somewhere down the line. I'm just not holding my breath. I think it's more likely we'll take in another congo grey at some point and Stella can get her physical affection from that bird. Max, being an only bird for the first few years of her life, seems to identify more with us.
I must add that I would love for them to nicely preen each other, and I do lecture both of them about how they would do a better job preening each other, since their beaks evolved to do that, rather than our relatively clumsy fingers. They're just not listening to us!