Cockatiels are amazing little creatures. I never thought about having one,until I read up about them on this wonderful and informative forum..I have always been "owned" by large parrots
BB came home to live with me and Amy when he was just a baby at 4.5 months old. Out of the 4 or 5 baby 'tiels the breeder had,Beebs was the one who chose ME, by jumping right on to my hand and demanding head skritches

I knew then and there he was the one!
You get back what you put into it,just like any relationship. But with parrots in general,they will give back 10x what you give them!
I know my "little boy...little boy" ( that's what he calls himself to me lol) loves me with his whole little heart! He sings at the top of his air sac every norning when I come home from work..he runs TO ME if I'm out of his line of sight,doing his flock calls. He will sit on my shoulder for hours,with his little beaky gently pressed against my cheek,while he serinades me with his songs.
He is also VERY smart! I am amazed on what he has learned. He talks well for a little guy..he wolf whistles as soon as he see's his Uncle DJ or Uncle Joe or Uncle David ( everyone is "uncle" to him lol)
His talking is pretty darn good too! He says HELLO but ONLY first thing in the morning..his favorite words are "little boy..little boy" " BB good boy" calls himself "Beebers"
He can whistle the Andy Griffith theme and Addams Family theme..mixing the two together lol. He has made his own special music. I can whistle a part of one of those theme songs and stop..and he'll pick up from where I left off,the he'll stop..and I continue lol...it's a game we play.
Some folks say Cockatiels aren't cuddly..BALONEY!

I can cup my hand around him and smother him in kisses,stroke his back,rub his beaky,give him head skritches etc etc..
Ok I'll stop bragging now! But I think you get the picture
BUT..as previously mentioned..YOU GET BACK WHAT YOU PUT INTO IT!
Do not expect miracles if you don't take the time with Cassy! and good luck!
Jim