diff --git a/CHANGELOG.md b/CHANGELOG.md
index 755591d..412acb4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,12 +6,10 @@
 * Add dependencies that were missing while using yarn
 
 ## 2.0.1
-
 * Comment out example "add_image_size" as it can be easily forgotten which leaves you with extra unused image size.
 * Add CHANGELOG.MD to track changes
 * Tidy up formatting using PHP-CS-Fixer (mostly spacing)
 * Update README.MD dependencies
 
 ## 2.0.0
-
 * Refreshed tooling using Elixir with lots of improvements
diff --git a/functions.php b/functions.php
index 88adc02..ae1a9c5 100644
--- a/functions.php
+++ b/functions.php
@@ -181,7 +181,7 @@ add_filter('tiny_mce_before_init', 'barebones_tiny_mce_before_init');
  * @param   int       $post_id post id
  * @param   boolean   $icon    if no image found, display icon
  */
-function get_post_thumbnail_url( $size = 'full', $post_id, $icon = false )
+function get_post_thumbnail_url( $size = 'full', $post_id = false, $icon = false )
 {
     if(!$post_id) {
         $post_id = get_the_ID();