Nested movieclips?

So I’m trying to simply nest some MCs and draw some squares within the nested clips.

nextDepth = this.getNextHighestDepth();

this.createEmptyMovieClip("mainMenu",nextDepth);
mainMenu.createEmptyMovieClip("menu1",nextDepth);
mainMenu.createEmptyMovieClip("menu2",nextDepth);
mainMenu.menu2._x = 250;

mainMenu.menu1.moveTo(0,0);
mainMenu.menu1.beginFill(0x000088);
mainMenu.menu1.lineTo(100,0);
mainMenu.menu1.lineTo(100,100);
mainMenu.menu1.lineTo(0,100);
mainMenu.menu1.endFill();


mainMenu.menu2.moveTo(150,0);
mainMenu.menu2.beginFill(0x000088);
mainMenu.menu2.lineTo(250,0);
mainMenu.menu2.lineTo(250,100);
mainMenu.menu2.lineTo(150,100);
mainMenu.menu2.endFill();

This is just my first step in a build and I wanted to test that the movieclips were nesting properly. The problem isn’t the squares but that the first movieclip isn’t displaying. And when I comment out the second MC (menu2) it displays fine.
If anyone would point how what I’m doing wrong or send me in the right direction with a tutorial, that would be wonderful.