Thinking about how to store objects in a game

Suppose I have a list of 100 enemies on the stage like this (pseudocode):


// init:
enemies = new Array();
for (i=0; i<100; i++) {
 temp = new Enemy(a, b, c);
 stage.addChild(temp);
 enemies.push(temp);
}

Now enemies is an array of all the enemies, so I can update all of their positions, and other properties, each frame. Is this a good way to do things? Because I just realized that I’m storing each enemy twice: One time in enemies Array and one time in stage.children. Maybe I should get rid of the enemies Array altogether, and just use stage.getChildAt() to update the enemies? Or am I missing something.