So, I am thinking about getting a cockatiel. And I was wondering, if me having other birds would impact on whether or not I could teach it too whistle? I plan on getting a boy, and I know there is no sure way that it would turn out to be a whistler to begin with, but if he was would I still be able to teach him to whistle? He wouldn't be housed with my two other birds. (IRN and GCC)