iTween scaling animation childed to hte camera in a FPS game...

Hi!. I'm instancing a prefab and then scaling smothly with a Ping Pong animation through iTween script.

I'd like to know how could I achieve the animated object recently instantiated and childed to my Camera of my First Person Controller,follows my look of the camera...

First: I instance my prefab. Second: I convert my instance in a child of my Camera of My First Person Controller. I've attatched properly the iTween script, in fact, I can watch my "image" GameObject scaling with the Ping Pong Loop. The code is here:

 image = Instantiate(array_of_images[num_im], transform.position-Vector3(0,0,3)*spacing , Quaternion.Euler( 0 , 0 , 0));
     
 image.transform.parent= Camera.main.transform;

Why doesn't work this?.