Didn't word my last post well enough! I was saying how it may be strange for tiels to mutilate, it sounds even stranger for finches.... However, Kiwi is a cockatiel (with a picture of her wing). I may see if I can get another image of it soon, to actually see for myself how her wing looks (since I haven't checked in months) and to see if she has stopped or???
In her previous home, she lived in a ferret cage with her family which was 18" x 18" x 46"... it's no longer in use now but here's an image of it! Oh and btw, it IS a California Cage....
In short, the cage was just WAY too small for 2 tiels, let alone 4... and on top of that, they were probably fed an inadequate diet, and the owners parents (especially father) were heavy chain smokers. The original owner was just a tad younger than me... and he used to really care for them and look after them.... but then he got into middle school and highschool.... and discovered sports and girls... and they were moved to this smaller cage.... and forgotten... and smoked around. On top of that, either the mother or daughter (I suspect mother) was laying eggs constantly, but they'd always crack. I haven't had her tested out, and I've had her for over a year now. She seems to be doing a LOT better, and most surprisingly she's been keeping her tail feathers!
She's not the first though... When I was 13, I was given a cherry headed conure who bit, screamed, and mutilated... at the time I didn't know of any vets, so couldn't even ask one for information... she's not the same bird now, but a lot of her issues deal with the fact that she was attacked by a ferret...
And to be honest though, I don't think Noel would have turned around so, without the help of Casey!
Sorry though to hear that you lost a larger bird to an issue you couldn't figure out! That must have been terrible!