Due to our temporary new addition, Rocky and Stella have been quite needy. I think they need reassurance that nothing will change for them. This is me being an armchair psychologist, but Max has been through this many times. She knows that bringing in a new bird will not upset her position in our flock. She has also never suffered any abuse/neglect/deprivation, as we're the only home she's ever known (other than her breeder).
On the other hand, Stella was the last bird we brought into our house, so this is the first time anything has upset the flock she's known with us. For the first couple of days that Steve was with us, she wouldn't come into the kitchen (normally her favorite place to be), eat her favorite foods, and was just acting rather strange.
Last night, she was in the kitchen and soliciting head pets from Thomas, who of course obliged her.
That seemed to make things better. After this long preening session, she seemed to bounce back, and the personality we've known returned.
Rocky had to come over while he was petting Stella.
Not getting the attention he wanted, he climbed up Thomas's pants, something he does only rarely.
Rocky was content perching on one of his hands while Thomas pet Stella with the other. My guess is that things will be back to normal by this weekend.