Calling function on main stage from within a movieclip

programming flash
1

Hi I’m new to as3 and going round in circles.
I want to make 5 buttons visible after a logo has animated.
I have a function called vis that successfully makes the buttons visible.
How do I call this from within the movie clip (instance name ‘logo’?)

first frame of main timeline code:
[FONT=Courier New]stop();

function vis () {
webMC.visible = true;
animMC.visible = true;
interactMC.visible = true;
dMC.visible = true;
soundMC.visible = true;
cvMC.visible = true;
contactMC.visible = true;
}

webMC.visible = false;
animMC.visible = false;
interactMC.visible = false;
dMC.visible = false;
soundMC.visible = false;
cvMC.visible = false;
contactMC.visible = false;

[FONT=Verdana]code on last frame of logo movie clip:

[FONT=Courier New]stop();[/FONT]
[FONT=Courier New]this.parent.logo.vis();[/FONT]
[/FONT]

[/FONT]