I think how similar parrots, and crows are is amazing. Both are highly social and intelligent animals. I joke that parrots are just more colorful versions of crows. New Caledonia crows have been known to make tools from the leaves of palm fronds to grab grubs in hard to reach places. Keas have also been to not only manipulate things with their beaks to get food but, also make tools. But, who is smarter?
Crows are known to be able to distinguish individual people from one another and can tell who is a friend or foe. They are even known to attack people who weren't so nice to them in the past. Parrots are the same way no?
Crows are known to mob predators so are cockatoos specifically the sulfur crested cockatoo. Sulfur crested cockatoos have been known to gang up on birds of preys. There are accounts of them dropping twigs on bat hawks in attempt to get them to leave.