diff --git a/app/Http/Controllers/Items/Items.php b/app/Http/Controllers/Items/Items.php
index a8d4f920e..88d753924 100644
--- a/app/Http/Controllers/Items/Items.php
+++ b/app/Http/Controllers/Items/Items.php
@@ -133,7 +133,7 @@ class Items extends Controller
             }
 
             if (isset($canDelete['invoices'])) {
-                $text[] = '<b>' . $canDelete['invoices'] . '</b> ' . trans_choice('general.items', ($canDelete['invoices'] > 1) ? 2 : 1);
+                $text[] = '<b>' . $canDelete['invoices'] . '</b> ' . trans_choice('general.invoices', ($canDelete['invoices'] > 1) ? 2 : 1);
             }
 
             $message = trans('messages.warning.deleted', ['type' => trans_choice('general.items', 1), 'text' => implode(', ', $text)]);
diff --git a/app/Models/Item/Item.php b/app/Models/Item/Item.php
index 9694eea1e..eaf593a1b 100644
--- a/app/Models/Item/Item.php
+++ b/app/Models/Item/Item.php
@@ -49,14 +49,14 @@ class Item extends Model
         return $this->belongsTo('App\Models\Setting\Tax');
     }
 
-    public function bills()
+    public function bill_items()
     {
-        return $this->hasMany('App\Models\Expense\Bill');
+        return $this->hasMany('App\Models\Expense\BillItem');
     }
 
-    public function invoices()
+    public function invoice_items()
     {
-        return $this->hasMany('App\Models\Income\Invoice');
+        return $this->hasMany('App\Models\Income\InvoiceItem');
     }
 
     /**
@@ -85,11 +85,11 @@ class Item extends Model
     {
         $error = false;
 
-        if ($bills = $this->bills()->count()) {
+        if ($bills = $this->bill_items()->count()) {
             $error['bills'] = $bills;
         }
 
-        if ($invoices = $this->invoices()->count()) {
+        if ($invoices = $this->invoice_items()->count()) {
             $error['invoices'] = $invoices;
         }