As smart as Sakura is, she'd figure out how to get in that bird cage in a few hours! =D
I bet that Sakura would LOVE for you to get a nice parakeet! LOL
I love birds! Especially parrots! Larger parrots have been found to have the intelligence level of a three year old child, so you can see how bad it is for them to be simply kept in a cage without a LOT of human interaction. If they have other birds with them, that's one thing, but if they are alone, they will become very neurotic and may even start feather picking (pulling out their own feathers) because they have to vent their frustration somehow, and sometimes it's via feather picking or even self-mutilation (picking at themselves until they open up a wound). I'd be happy to answer any questions you have that fall within my scope of experience. :)
To keep this on topic, since this IS the cats board, it is important to make sure, especially if you have large parrots, that your cats become "bird savvy", not only for the safety of the birds, but also for the safety of the cats! While the natural reaction is to worry that a cat would harm a bird, and in the case of small birds this is a significant worry, a large parrot such as a macaw could seriously hurt or even kill a cat, so never leave the two unattended.
Ghilly
Wow, Ghilly, I never knew all that! I know who I'm going to come to from now on when I have any questions about birds! We might get another parakeet one of these days, we'll see. :)
Budgies are members of the parrot family, and as such, are given to theatrics just like large parrots are. When your budgie screams, don't scream back for him to "shut up!!!!", because that will just incite him to yell even more.
When he screams, go over to the cage and try talking to him in a calm voice, repeat a phrase like "you're a pretty bird" until he calms downm, and them tell him what a good boy he is. Unless he is screaming uncontrollably, don't cover him or put him in a room by himself. Being alone is torture for a bird. Birds are probably some of the most social creatures on the planet, and this will not only eventually make for a completely neurotic bird, it will only make the screaming worse in the long run.
Make sure he has plenty of toys in his cage to play with. Budgies (all parrots, actually) are highly intelligent and get bored easily. Boredom leads to more screaming, so keep three or four different toys in the cage at all times, and switch them off with three or four OTHER toys each week. This way he never has a chance to get bored with any particular toy. Keep a television on or a radio playing for your bird. He will appreciate the music and entertainment, and he may even learn a few words. My green cheek conure has learned quite a few phrases from television. He has a vocabulary of about 150 words right now, which is pretty impressive for a conure.
Something else to keep in mind is that birds view their humams as part of their flock, and they relate to them in the same way as they would other birds. When your bird reaches sexual maturity, there is a chance that, if it's a female, it will bond more closely with a male member of the family, and if it's a male, it will bond more closely with a woman in the house. If you are holding the bird, be it male or female, and someone else comes near you, your bird may perceive this to be a threat, and he or she may bite you. In nature, this would be the bird's way of getting his mate out of harm's way, and that's the message he or she is trying to convey to you.
Birdies are strange little characters psychologically. Once you understand their little foibles it's a lot easier to relate to them and understand them.
Ghilly
I think you may have stumbled onto the Cat forum by mistake. There is a bird forum on this site, too. They may be able to help you. I'm afraid I don't know that much about birds! I did have a parakeet for a few years. What usually calmed him down was when we'd put a light blanket over his cage. I guess it signals them that it's time to sleep or something. Try the bird forum, though. There might be others on there who can help you out! Good luck! :)