functions.php

<?php

add_filter( 'be_subpages_widget_args', 'be_subpages_menu_order' );
/** 
 * Subpages Widget - Sort by Menu Order 
 *
 * @param array $args
 * @return array
*/
function be_subpages_menu_order( $args ) {
	$args['sort_column'] = 'menu_order';
	return $args;
}