Getting child content

I would like to suggest you to use WP_Query to fetch pages from db:

$the_query = new WP_Query( array( 
    'post_parent'    => $page->ID,
    'orderby'        => 'menu_order',
    'order'          => 'ASC',
    'posts_per_page' => 3,
) );

while ( $the_query->have_posts() ) :
    $the_query->the_post();

    ?>
    <div class="span4">
        <h2><a href="https://wordpress.stackexchange.com/questions/83491/<?php the_permalink() ?>"><?php the_title() ?></a></h2>
        <?php the_content() ?>
    </div>
    <?php
endwhile;

wp_reset_postdata();

Also be careful! You use $page variable at first line of your snippet as already defined, and then you re declare it again when you use it in the foreach loop at the 2nd line of your snippet.

error code: 523