I have not posted on this thread yet, but my daughter (Riddick07) has been telling me the updates and what was going on. I wanted to avoid posting because as a mom with an animal crazy kid, I thought my opinion might be just a little too loud or pushy
You mentioned your daughter being an old soul, if no one else here can understand that statement, I can... its a phrase I've used to describe Victoria most of her life. While she is now 23 (just had a birthday Monday), when she was about 12 years old I was able to afford to purchase her the first horse, like your daughter with birds, she had been horse crazy all her life but it wasn't until she was around 10 that I could afford her to get into riding. At 12, it was suggested that a horse we had to meet was not even 4 years old at the time and dead green... 99% of people thought I was insane for even considering letting a kid with little riding experience sit on the back of a green, barely broke horse, long let consider buying him. But, following my gut, we drove down to TN and the day she met Chip, she rode him bareback and he followed her around like a big puppy (a really big BIG puppy). Fast forward to today, Chip has been in the family for almost 11 years (April is his birthday and when he came home). They went to Devon together and we have probably hundreds of photos of them thru the years, both serious riding and her sitting on him backwards, laying on his back and just all sorts of goofy things. While I am sure there are lots of other wonderful horses we could have added to our family, sometimes the right animal does not fit what anyone would say is 'typical'. In case you had not heard anyone yelling at their computer, I have been hoping all along you would follow your instinct and your daughter's heart and bring the sun home. Might he have issues at some point, maybe scream a little loud or bite harder then the cockatiel, maybe, maybe not... But in the long run, I would almost guarantee your daughter will have a friend for life that the cockatiel may never be. Okay, admit, I'm not a cockatiel fan... they are pretty birds, but for an interactive, 'fun' bird, they just don't make my list. I was like you for years, never was a bird fan, they were always too much work, too noisy, too messy, just not a loveable 'real' pet (my daughter still likes to remind of that and laughs at me). Her first birds were cockatiels and honestly, they were exactly what I always thought, never was impressed with them (still not)... but when she got the first green cheek conure, have to admit, little Monkey bird won me over. So much that we added another green to the family after her. Then this summer my daughter spent the summer on Semester at Sea traveling Europe and it was after that both my husband and I were hooked on the conures. We took care of the cockatiels, but the conures were out with me most of the time I was home. There is just something so much more companion about them then I ever saw in the cockatiels.
Anyway, the point of all my babble... ask the cockatiel breeder if you can return the tiel and head straight to the pet store

If all of you have enjoyed the sun at the store, just imagine the interaction when he's hanging out with you on the sofa at night with a basket of toys. Loki is the sun in our home and he's a new addition, but he's got the biggest personality and to make sure he doesn't develop any bad habits, he is very well socialized, spends time with everyone and interacts differently with each person. He loves to pull at the stubble on my husband's chin when he needs to shave, he'll sit on my shoulder and croak at me and play with my earring or climbs down my lap and chews on my laptop (something he never tries with his mother's laptop!!). He's a character and will hop across the sofa from one person to another... is he just a super special sun, nope, don't think so, we've just made sure he is well socialized and talks to everyone so the bad habits never develop. Don't let other people's stories scare you off from what you feel is right for your family. Just because one person has a sun that is obsessed with them and overly bonded, doesn't mean yours will be. Your daughter sounds like an amazing little person, I am guessing with the same love and guidance, any bird you add to your home will be just the same.
Now that I've taken a whole page to babble on... I hope you follow that gut instinct and the signs from the universe...
Good luck!!
Jen
PS - Don't mean to offend anyone in this post.... And those who say a budgie or parakeet have a pleasant sound, the tiniest bird. my little Cam, is absolutely the most annoying sounding bird you could meet. The sun doesn't scream or go on and on, but that dang budgie... well lets just say he's lucky he is so pretty....