SQL query not displaying the product in each sub category

I am trying to display a product on each category starting from the top parent category all the way down to the category. I have my db setup like this:

CATEGORY TABLE:
id  |  parent_id   |  root_cat   |  name
5       37              0            bulbs
45      5               0            standard auxiliary
289     45              5            standard
297     289             5            5W

Now this is the products table table:

id    |   name    |   cat
470       bulb 5w      297

And this is happening, when i click on the bulbs category i see the product just fine, but when i click in the sub category standard auxiliary i do not see the product. But if i go another level to standard i can see the product again and also if i click on the 5W cat i also see the product. So the problem is only on the standard auxiliary category.

This is the method i am using to retrieve the data: $table_2 is the products table and $table is the category table.

public function getProductsWhereParentIdis($cat) {
        $check = $this->checkCategoryChildren($cat);
        if($check) {
            $query = "
            SELECT * 
            FROM categories 
            INNER JOIN products 
            ON products.category = categories.id 
            WHERE categories.id = '".$this->db->escape($cat)."' 
            OR categories.parent_id = '".$this->db->escape($cat)."' 
            OR categories.root_category = '".$this->db->escape($cat)."'";   

            return $this->db->fetchAll($query);
        } else {
            $query = "SELECT * FROM {$this->table_2} WHERE category = '".$this->db->escape($cat)."'";

            return $this->db->fetchAll($query);
        }


    }

and this method is just to check if a product has a parent:

public function checkCategoryChildren($id = null) {
        if(!empty($id)) {
            $query = "SELECT * FROM {$this->table} WHERE parent_id = '".$this->db->escape($id)."' ORDER BY view_order ASC";

            return $this->db->fetchAll($query);
        }
    }

Really looking forward to anyones suggestion as to why i can see the product in all the categories but one, thank you.

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