Horses are always different in new homes (they always test, even in small ways and I've seen horses that were angels for 20+ years in one home turn in 9 months in a new home) and they're like parrots in quite a few ways. To begin with, they're a prey animal that relies on their social group for survival.
Do you miss that cockatoo? I had a similar experience when I was 14 and my mom brought me with to help her house clean these multi-millionare's house. They decided to buy an african grey to go in the huge, old, terrible wrought iron cage suspended from the vaulted ceiling in the main entry room. I took on the task of cleaning his cage (which was not easy because there was no sliding bottom and it was a round cage) and ended up bonding with him. I remember feeling like the world when one day he crawled from my arm onto my chest for scratches, puffed up, and spread his little wings over me.
With others, he had normal bird issues and I tried to tell them what to do to deal with it. I remember them totally disregarding what I said, hiring an animal behaviorist who cost $60 an hour to tell them the same thing, with the exception that I was no longer allowed to see Merlin because he was too attached to me.
The man who fought so hard and paid so much to win that parrot's trust and banned me from seeing him sold him a couple years later because his wife told him it was her or the bird.
So yeah, I've seen the bird attachment/adjustment thing
