Good for you for teaching your kids! I wish more adults would do so. Even Cah'ya, my Ekkie who came to me as a baby and has never been even slightly mistreated, knows the difference between what I say when I'm frustrated with her and what I say when I am not. Whenever she would bully the other birds, I would say, "Cah'ya, why you gotta be such a brat?" or "Oh, stop being such a b**** to everyone else." I always said this is a good humored tone of voice--more chiding than actual anger.
But one day, she was playing with her trash can toy in her cage. She had discovered a few weeks prior that her voice sounds different in the trash can than outside of it, so she had been spending a lot of time saying something in the can and then saying it again out of the can. All of the sudden, she put her head in the trash can and in this angry demon voice she said, "WHY YOU GOTTA BE SUCH A BRAT, CAH'YA!" Then she pulled her head out and in a sweet voice said, "I love you, Cah'ya!" Then she put her head back in and in that same angry demon voice she said, "QUIT BEING SUCH A B****, CAH'YA!" Then she pulled her head out and in a sweet voice said, "You're so beautiful, Cah'ya!" She did that for several minutes, saying the scolding things I'd said to her in the past in a really angry, ugly voice in the trash can, and then saying the sweet things I've said to her out of the trash can in a sweet, loving tone. Like I said, I have never used such an ugly tone of voice with her, but she knew the different, anyway.
On one hand, it made me laugh so hard I was in tears, but on the other hand, it made me really sad, because that's how she was perceiving my scoldings, and it was a real wake up call that these birds understand a LOT more than we give them credit for. They internalize their caretakers' emotions, just like human children do. So if Cah'ya, who has only ever known love, can be that affected by those super minor negative experiences, imagine how affected these birds are who are in abusive situations. It makes me cry just thinking about it.