diff --git a/classes/Category.php b/classes/Category.php
index f3229ab9b..fe4083a8d 100644
--- a/classes/Category.php
+++ b/classes/Category.php
@@ -744,17 +744,17 @@ class CategoryCore extends ObjectModel
 	public static function getChildren($id_parent, $id_lang, $active = true, $id_shop = false)
 	{
 		if (!Validate::isBool($active))
-	 		die(Tools::displayError());
+			die(Tools::displayError());
 
-        $query = 'SELECT c.`id_category`, cl.`name`, cl.`link_rewrite`, category_shop.`id_shop`
+		$query = 'SELECT c.`id_category`, cl.`name`, cl.`link_rewrite`, category_shop.`id_shop`
 		FROM `'._DB_PREFIX_.'category` c
 		LEFT JOIN `'._DB_PREFIX_.'category_lang` cl ON (c.`id_category` = cl.`id_category`'.Shop::addSqlRestrictionOnLang('cl').')
 		'.Shop::addSqlAssociation('category', 'c').'
 		WHERE `id_lang` = '.(int)$id_lang.'
 		AND c.`id_parent` = '.(int)$id_parent.'
 		'.($active ? 'AND `active` = 1' : '').'
+		GROUP BY c.`id_category`
 		ORDER BY category_shop.`position` ASC';
-
 		return Db::getInstance(_PS_USE_SQL_SLAVE_)->executeS($query);
 	}
 
diff --git a/controllers/admin/AdminShopController.php b/controllers/admin/AdminShopController.php
index 88148abbe..82b876d17 100755
--- a/controllers/admin/AdminShopController.php
+++ b/controllers/admin/AdminShopController.php
@@ -548,7 +548,7 @@ class AdminShopControllerCore extends AdminController
 				$this->errors[] = Tools::displayError('An error occurred while creating object.').
 					' <b>'.$this->table.' ('.Db::getInstance()->getMsgError().')</b>';
 			}
-			 /* voluntary do affectation here */
+			/* voluntary do affectation here */
 			else if (($_POST[$this->identifier] = $object->id) && $this->postImage($object->id) && !count($this->errors) && $this->_redirect)
 			{
 				$parent_id = (int)Tools::getValue('id_parent', 1);
@@ -569,8 +569,8 @@ class AdminShopControllerCore extends AdminController
 		$this->errors = array_unique($this->errors);
 		if (count($this->errors) > 0)
 		{
-            $this->display = 'add';
-            return;
+			$this->display = 'add';
+			return;
 		}
 
 		// datas to import
@@ -601,11 +601,13 @@ class AdminShopControllerCore extends AdminController
 		if (empty($selected_cat))
 		{
 			// get first category root and preselect all these children
-			$root_category = Category::getRootCategories();
-			$children = Category::getChildren($root_category[0]['id_category'], $this->context->language->id);
-			$selected_cat[] = $root_category[0]['id_category'];
+			$root_categories = Category::getRootCategories();
+			$root_category = new Category($root_categories[0]['id_category']);
+			$children = $root_category->getAllChildren($this->context->language->id);
+			$selected_cat[] = $root_categories[0]['id_category'];
+			
 			foreach ($children as $child)
-				$selected_cat[] = $child['id_category'];
+				$selected_cat[] = $child->id_category;
 		}
 		if (Shop::getContext() == Shop::CONTEXT_SHOP && Tools::isSubmit('id_shop'))
 			$root_category = new Category($shop->id_category);