diff --git a/sidebar.php b/sidebar.php
index bb082b4..4f18bb5 100644
--- a/sidebar.php
+++ b/sidebar.php
@@ -21,7 +21,7 @@
 //
 function process_cat_tree( $cat ) {
  
- $args = array('category__in' => array( $cat ), 'numberposts' => -1, 'orderby' => title, 'order' => ASC);
+ $args = array('category__in' => array( $cat ), 'numberposts' => -1, 'orderby' => 'title', 'order' => 'ASC');
  $cat_posts = get_posts( $args );
  
  if( $cat_posts ) :