Fade in Fade off buttons

Hi,

I am working on my portfolio site. I have a probelm with my navigation.

I have 3 buttons profile, about and contact.
what I am doing is when I click on profile all the buttons should fade off first and then only the about and contact button should appear on the scene.

please see my code.

bt_1.onRelease = function(){

this.onEnterFrame = function(){
if(bt_1 >= 0){
bt_1._alpha -= 10;
}
if(bt_2 >= 0){
bt_2._alpha -= 10;
}
if(bt_3 >= 0){
bt_3._alpha -= 10;
}

}

This is the code for fade off all the buttons. Now I want to fade in only the bt_2 and bt_3 buttons. Is it possible