he/she is about 12 weeks old. i'm not sure how old they need to be before i can tell but i'd like to know if anyone can help. i've provided two photos if it helps.
i've heard that females are really sweet and more affectionate, which is what mine is like.

http://s696.photobucket.com/albums/vv324…

http://s696.photobucket.com/albums/vv324…

thanks in advance. xo

Looks like a whiteface cinnamon pearl cockatiel. Unfortunately, these aren't the easiest mutations to sex. A few things you can look for is whether or not your bird has markings under the wings or the tail. Males will lose these markings and females will retain them. Because your bird carries the pearl gene (those are the markings you see on his wings) this may give you another clue to his/her gender. Males will lose the pearl markings after a few molts, and females will not. But because your cockatiel is not a full pearl, if he is male he may still not lose all of the pearling. I have a pearl pied male (was DNA sexed) and he has still retained many markings. Your best method is to get a DNA test done.

Have studied cockatiel mutations and sexing methods

Blood test is the only way to tell sex of a cockatiel.