I personally would never pierce my babies ear, i will tell you why, one they have no choice in the matter,and yes they will forget the pain, but still she will feel it just the same, i never had mine done until i was 18 and my daughter when she was about ten, either way you feel the pain and forget it, so i don't really see the reasoning in what you are saying, however i do know that certain cultures do it at a young age, but to me that is slightly different, have you asked why you wish to really do it, because it looks pretty you think.

I just think everyone should have the right to make a choice when they are old enough to,as to whether they want piercings in their ears, of course she can always let them grow over the holes if she does not like them when she is older,but i just think you would be better waiting, also i can only imagine what a hassle it would be to take care of at such a young age, however it is of course your'e personal choice, she is your child, and you make the decisions for her.