child twenty eleven functions single sidebar

add_filter('body_class', 'blacklist_body_class', 20, 2);
function blacklist_body_class($wp_classes, $extra_classes) {
if( is_single() ) :
// Filter the body classes, and remove 'singular' when single post
    if (!in_array('singular', $wp_classes)) : continue;
    else:
      foreach($wp_classes as $key => $value) {
      if ($value == 'singular') unset($wp_classes[$key]);
      }
    endif;
endif;   // Add the extra classes back untouched
return array_merge($wp_classes, (array) $extra_classes);
}