Instance name in AS3 when using addChild();

programming flash
1

I attached my “menu” movie clip to stage using addChild();. Inside menu there is four buttons, which have instance names but main MovieClip “menu” doesn’t. I have a difficulties to access those buttons using AS3. Could you please help me. this is a code I used: - PLEASE FIX IT/ thx

// Menu animates in:

var menu_anim:menu = new menu();
addChild(menu_anim);
new Tween(menu_anim,"alpha",Strong.easeOut,0,1,10,true  );

Now when i try to use

menu_anim.name = “menu_mc”;
var currentPage:MovieClip = menu_mc.btn_permanentmakeup_mc;

… i am getting an error : 1120: Access of undefined property menu_anim.

Could you please help me hot to access “btn_permanentmakeup_mc” movie clip inside “menu” movie clip?