Model troubles

Well i have 2 tables one called item and another called item_img.

item has many item_imgs and item_img belongs to 1 item. Item_img has a column called default which is a boolean. If that img is true then thats the image that's going to appear when i'm listing every item.

when i execute $items=Item:find(), i get every item with every img that they have assosiated, now my question is how can i get the default img?

i could do it with a foreach item->itemImg but that doesnt seem so elegant; ive been trying to do

public function getDefaultImg()
    {
        return ItemImg::findFirst(
            array("item_id =  ?1 and default =  ?2",
                "bind"=>array(1=>$this->id,2=>1)));
    }

but im not really sure how to check if i got the img im searching for because when i try to pass it on to the view by doing $this->view->items=$items

it just throws an eror saying Access to undefined property Item::img since i dont have the attribute img define in the model, when i add it to the model i still dont get the image.

img doesnt map to any column in my database thats why i didnt have it so im not really sure if its correct to leave it in my model.

heres my 2 models

class Item extends \Phalcon\Mvc\Model
{
    public $id;

    public $name;

    public $price;

    public $stock;

    public $details;

    public $last_modified;

    public $created_at;

    public function initialize()
    {
        $this->hasMany("id", "ItemImg", "item_id", array(
            'foreignKey' => array(
                'action' => Relation::ACTION_CASCADE
            )
        ));
    }

...

class ItemImg extends \Phalcon\Mvc\Model
{
    public $item_id;

    public $hash;

    public $img_type;

    public $route;

    public $default;

        public function initialize()
    {
        $this->belongsTo("item_id", "Item", "id");
    }
}

heres the controller action

    public function indexAction()
    {

    $items=Item::find();
    foreach($items as $item){
        $item->img=$item->getDefaultImg();
    }

    $this->view->items=$items;
    }