<?php
$pages = get_pages(array('post_type' => 'page','sort_column' => 'menu_order','sort_order' => 'ASC','child_of' => 765));

foreach($pages as $post)
{
setup_postdata($post);
$fields = get_fields();
?>
        <p><?php echo $fields->start_date; ?> <a href="<?php echo get_page_link($post->ID) ?>"><?php echo substr($fields->event_title,0,24) . "..."; ?></a></p>
<?php
}

wp_reset_query();
?>

$pages = get_children(array(
   'numberposts' =>1,
   'post_parent' => $heading_page->post_id
   ));