$wpdb->prepare returns empty array

Try with:

function getComponents($page_id, $currentLanguage) {
       global $wpdb;
       $result = $wpdb->get_results($wpdb->prepare( "
          SELECT id, post_content, post_title, post_excerpt, post_name, m1.meta_value AS 'template', m2.meta_value AS 'home_description'
          FROM {$wpdb->posts} p
          JOIN wp_term_relationships r ON p.ID = r.object_id
          JOIN wp_terms t ON r.term_taxonomy_id = t.term_id
          WHERE t.slug=%s AND post_parent = %d AND post_type="page" AND post_status="publish"
          ORDER BY menu_order ASC ",
          $currentLanguage, $page_id ), OBJECT_K );
       return $result;
    }