Problem with concatenating names

Here’s the problem:

I have written a simple mp3 player as a custom class, SimpleMp3Player. All it does is load and play a single mp3, which is passed in to the constructor.

My main class has a function LoadMedia() which creates n instances of this class, names them player_1 through player_n and places them in various locations.

I am also trying to write a RemoveMedia() function to get rid of all the instances. I can brute-force remove them all by hard coding removeChild(player_1), *removeChild(player_2) *etc. through removeChild(player_n).

But of course, I would much rather use a loop to do this. I tried this:[INDENT]for (var i:int = 0; i<21; i++) {
removeChild(getChildByName([“player_”] + (i+1)));
[/INDENT]but I get this error:
TypeError: Error #2007: Parameter child must be non-null.
at flash.display.DisplayObjectContainer/removeChild()

I have tried every variation of the syntax I can think of with no success. What am I doing wrong here?