// Use a parent category slug if it exists function child_force_category_template($template) {     $cat = get_query_var('cat');     $category = get_category($cat);      if ( file_exists(TEMPLATEPATH . '/category-' . $category->cat_ID . '.php') ) {         $cat_template = TEMPLATEPATH . '/category-' . $category ->cat_ID . '.php';     } elseif ( file_exists(TEMPLATEPATH . '/category-' . $category->slug . '.php') ) {         $cat_template = TEMPLATEPATH . '/category-' . $category ->slug . '.php';     } elseif ( file_exists(TEMPLATEPATH . '/category-' . $category->category_parent . '.php') ) {         $cat_template = TEMPLATEPATH . '/category-' . $category->category_parent . '.php';     } else {         // Get Parent Slug         $cat_parent = get_category($category->category_parent);          if ( file_exists(TEMPLATEPATH . '/category-' . $cat_parent->slug . '.php') ) {             $cat_template = TEMPLATEPATH . '/category-' . $cat_parent->slug . '.php';         } else {             $cat_template = $template;         }      }      return $cat_template; } add_action('category_template', 'child_force_category_template'); 

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