Object Fallow Y axis !

hey guys i was wondering if you could please help me. Basically i have two cubes one that contains my Mouselook script and one that has nothing. Now what i want to do is if the player looks up and down on the Y axis i want the other cube to fallow the up and down directions can someone please help me thank you :) I would really appreciate it.

Here is my mouse look script:

     public enum RotationAxis {MouseX = 0, MouseY = 1}
          
          var RotationAxisRotationXY = RotationAxis.MouseX | RotationAxis.MouseY;
          
          //We are defining the variables needed for our X axis motion. This will include 
          //Sensitivity and the minimum and maximum of the x axis rotation 
          
          var sensitivityX : float = 400f;
          
          var minimumX : float = -360f;
          
          var maximumX : float = 360f;
          
          var RotationX : float = 0f;
          
          var OriginalRotation : Quaternion;
          
        var Game : Transform;
         
          // Now lets set the variables for the y axis so the player can then look up and down
          // using the mouse.
          
          var RotationY : float = 0f;
          
          var minimumY : float = -25f;
          
          var maximumY : float = 25;
          
          var sensitivityY : float = 400f;
 
     
 function Update () {
 
    
 
       if(RotationAxisRotationXY == RotationAxis.MouseX){
        
           RotationX += Input.GetAxis("Mouse X") * sensitivityX * Time.deltaTime;
           
               
               
               RotationX = ClampAngle (RotationX, minimumX, maximumX);
               
               OriginalRotation = XQuaternion = Quaternion.AngleAxis (RotationX , Vector3.up);    
              
              transform.localRotation = OriginalRotation * XQuaternion;
              
 
             }
             if(RotationAxisRotationXY == RotationAxis.MouseY){
             
             RotationY -= Input.GetAxis ("Mouse Y") * sensitivityY * Time.deltaTime;
             
             RotationY = ClampAngle (RotationY, minimumY, maximumY);
             
             OriginalRotation = YQuaternion = Quaternion.AngleAxis (RotationY, Vector3.right);
             
             transform.localRotation = OriginalRotation * YQuaternion;
             
         
             
             }
         
            
 
     
          
 }
 
         
                 
     
     
     static function ClampAngle (Angle, min, max): float {
     
     
         if(Angle < -360){
         Angle += 360;
         
         }
         if(Angle > 360){
         
         Angle -= 360;
         }
         
         return Mathf.Clamp (Angle, min,max);
     }

The variable var Game : Transform; is a reference to the cube that is meant to fallow the other cubes Y axis :) Thank you in advance :)