public function is_orphan() {

		$statuses = array( 'publish', 'future', 'draft', 'pending', 'private', 'auto-draft' );

		foreach ( array( 'course', 'section' ) as $parent ) {

			$parent_id = $this->get( sprintf( 'parent_%s', $parent ) );

			if ( ! $parent_id ) {
				return true;
			} elseif ( ! in_array( get_post_status( $parent_id ), $statuses, true ) ) {
				return true;
			}
		}

		return false;

	}