Welcome Shimona, thanks for a lovely introduction and please accept my condolences for your loss of Julia. You've the best of intentions for William and, as wrench13 suggested, two distinct choices.

It is possible to tame a non-hand fed cockatoo with patience, time, and love. Some techniques for establishing trust and bonding: Tips for Bonding and Building Trust If you find progress too slow or William simply does not respond, finding a suitable mate next best solution. I'm not sufficiently familiar with galahs to recommend alternative species. Perhaps another similarly sized cockatoo?

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