trigger not triggering

I have a sphere trigger as a child of a game object who has an animation attached.

the idea is to have the user walk into the trigger and it tells it's parent to play the animation. but its not playing. I don't get it. here's the code that is on the Sphere trigger:

function OnTriggerEnter (other : Collider) 
{
     transform.parent.animation.Play("MyAnimation");
}

The parent of a transform is itself a transform, so you are trying to trigger the transform's animation, not the GameObject's animation. Try:

 transform.parent.gameObject.animation.Play ("MyAnimation");