I don't want to be rude or harsh to you, but your post is extremely frustrating because you've already been told that there is no way to guarantee that ANY PARROT is going to ever speak/talk, regardless of their species...The Congo African Gray is the best talking parrot species in the world, and many of them never say a word...You just shouldn't buy a parrot because you want a pet who talks.
I don't have a clue what your motivation for buying any pet bird at this point is, as you've somehow been able to re-home multiple birds already that you've had for at least months...The Alexandrines, the Sulfur Cockatoo, etc. Now you're not satisfied with this Cockatoo either because it doesn't talk either...It's beyond me how you can take in a baby parrot of any kind and just "take it back" like you're trading-in a used car or something...You don't get a pet parrot because you want a neat pet that can talk and you can show-off to your friend. You get a pet parrot because you want an intelligent, affectionate, loving companion to add to your family and that you can love and have a bond with for decades...If you want something that talks and mimics you then the answer is not buying continual birds until you get one that talks, because you may NEVER get one that speaks...
And honestly, it's very obvious that you haven't done ANY RESEARCH AT ALL prior to buying these birds, because #1) Your complaint about the sulfur Cockatoo was that "he was destructive and he screamed all the time...Are you serious? You had a Cockatoo with the intelligence of a 4 year-old human toddler locked inside a cage too small for a Cockatiel, bored to tears, with an owner that only cares about whether or not he can mimic his speech. Why do you think he was screaming? Cockatoos are known for being extremely neurotic, destructive, and screaming non-stop if you don't provide them with hours and hours each day of love, affection and give them non-stop foraging activities and jobs to do to keep their brains occupied...And that includes the one you have now. If you had done any research at all you would have known this...and then #2) Cockatoos are not really known in-general to be great talkers...
I'm not trying to be mean to you, but you seemingly have no idea what you're doing, and you're treating living, breathing birds with the IQ's of small children like they are some inanimate objects that you can take back to the store if you decide you don't want them anymore...And I certainly hope that your Alexandrines and the Sulfur Cockatoo (and any other birds you've done this with) were all re-homed to loving, responsible homes or Avian Rescues and not killed or just set-free into the wild...
I realize that I don't know where you're from in the world, and you may have different cultural beliefs and ideas of what "pets" are, but the reason you're such an odd case is that all you care about is whether they talk or not...I don't get that. I'll say it one more time just to make myself feel better...There is absolutely no way to know if ANY parrot you buy is going to EVER talk. It doesn't matter what species of parrot you buy,
what gender, etc. You can play a recording of yourself saying "hi" every minute of every day, but that bird may never say a word...So if this is truly the ONLY REASON that you want a pet bird, then you just shouldn't have a pet bird...
****I'm going to try to be very honest with you and try to help you here now by giving you some really good advice, simply for the sake of that poor Cockatoo you have trapped in that tiny little cage...So please listen and take this seriously and to heart...No parrot, least of all a Cockatoo with the intelligence and needs of a 4 year-old human child, is going to say a word for you if they are not happy and healthy. And the way to have a happy, healthy parrot is to provide them with an adequately-sized cage that they can move around it, that you can hang between 6-10 different types of toys in at any given time and still have room to open their wings up the entire way and not touch the bars, and most-importantly to provide them with at least 5-6 hours each and every single day of out-of-cage-time where you are their "flock-mate", you give them love and attention, you read to them, you play with them, you do puzzles with them,
you cuddle with them, etc. Your bird is inside of a cage that is smaller than the cage I have for any of my very small parrots, including a Green Cheek Conure and a Cockatiel...You need a cage that is at least 5 to 6 times that cage or larger for that Cockatoo to be remotely healthy and happy...And ALL species of Cockatoos, Macaws, African Grays, and every other parrot need tons of toys, foraging activities, and love and attention to stay happy and healthy...Otherwise they aren't going to make any sounds except for screaming, as you've already found out...
I wish you the best, but I feel so sorry for your poor Cockatoo. That bird deserves love, affection, and adequate care, whether he/she EVER says a word or not. Parrots are not like any other type of "pet"; they are not dogs or cats, or reptiles, or rodents...They are the equivalent of having a "pet" Primate, like a Monkey, a Lemur, etc. That's how intelligent they are, and how much attention and work it takes to keep them happy and healthy...It's also the reason why most Cockatoos, Macaws, Grays, Amazons, etc. end-up Plucking themselves bald and Self-Mutilating...
I highly suggest that you either fully, 100% commit yourself to this current Cockatoo that you have, meaning that you love this bird with all your heart, you make it a member of your family, you spend the money to get it what it needs to stay happy and healthy including a much, much, much larger cage, lots and lots of different toys and foraging activities, an adequate, healthy, low-fat daily diet, and Avian Vet care, and most of all you spend the time with it every single day outside of it's cage that it needs to stay healthy and happy, just like a child needs, because that's what it is, it's a child. And you do all of this regardless of whether it ever speaks a word...And you realize that you're going to have to do this for decades and decades!!! And if you cannot commit to doing all of these things regardless of whether it speaks a single word ever, then you need to find he/she a new, responsible, loving home that will...And then PLEASE do not go out and buy another bird ever again!!! And once more...The only way you're EVER going to get a bird that is guaranteed to talk is if you adopt an adult parrot that is already taking...And even if you do that, you would still need to keep-on providing the bird with the same love, affection, time, diet, space, toys and activities, etc. that it's former owner did, because if you don't and you just lock it inside of a tiny cage with nothing to do all day, it won't continue to keep talking, it will become depressed, unhealthy, and start to scream and pluck itself...
Being as nice as I can be to you, the bottom-line is that you have been trying to buy a pet parrot for entirely the WRONG REASON, and obviously, you have to agree that it's not working out for you at all...And most of all it's not been working out for the multiple birds you've already abandoned...
