How to add hearts as I pick up healths?

I have a script that controls my players health. This means that if I fall off the map I lose a life and a Texture2D of a heart is reduced, you start with 3 hearts. I'm trying to whenever the player picks up a heart, its life increases, that part is working, but I can't seem to figure how to also increase the Texture2D. I've tried many ways, but nothing worked. I even tried reversing the damage part to see if it worked, but no, so I left it as it was.

Health Script:

 #pragma strict
 
 var lives = 3; //amount of health of the player
 var livesTexture : Texture2D[]; //the texture for the health
 var livesTextureSize = 30; //size for the health texture
 
 function Update () {
     if (lives == 0){
         Application.LoadLevel("Scene_1");
     }
 }
 
 function OnTriggerEnter (other : Collider) {
     if (other.tag == "Enemy"){
         if (lives-1 >= 0){
             livesTexture[lives-1] = null;
             lives -= 1;
         }
     }
     
     if (other.tag == "Falling"){
         if (lives-1 >= 0){
             livesTexture[lives-1] = null;
             lives -= 1;
         }
     }
     
     if (other.tag == "Heart"){
         if (lives+1 <= 3){
             livesTexture[lives+1] = null; //I know it doesn't work, but it was worth I shot, I guess
             lives += 1;
             Destroy(other.gameObject);
         }
     }
 }
 
 function OnGUI () {
     var livesTextureRect = Rect (10, 5, livesTextureSize, livesTextureSize);
     for (var i : int = 0; i < lives; i++){
         GUI.DrawTexture (livesTextureRect, livesTexture[i], ScaleMode.ScaleToFit, true, 0.0f);
         livesTextureRect.x += livesTextureSize + 10;
     }
 }

Taken Damage: As you can see, the hearts (at the top left) was reduced and my life counter (at the Inspector) was alse reduced.

Restored Health: Here's the problem, the life counter (at inspector) was increased when I picked up the heart, but the hearts stayed at two (top left).