Widget – only display child categories

Get the PHP Exec Widget by Otto.
http://wordpress.org/extend/plugins/php-code-widget/

Then put this code in one of the widgets:

<?php
if (is_category( )) {
  $cat = get_query_var('cat');
  $parent = get_category ($cat);
  if ($parent->parent) {
    wp_list_categories ('child_of=' . $parent->parent);
    } else {
    wp_list_categories ('child_of=' . $cat);
  }
}
?>

Thanks!!
Very usefull!!!

Can i remove the item “Categorie” which is displayed just above the child categories?
It has probembly something to do with the css, because i cant find it in the php code…
http://www.campingdestriene.nl/website/category/verblijfsmogelijkheden/camping-algemeen