Child list + excerpt

/**
* Children list
*/
function subpage_peek() {
    global $post;

    //query subpages
    $args = array(
        'post_parent' => $post->ID,
        'post_type' => 'page'
    );
    $subpages = new WP_query($args);

    // create output
    if ($subpages->have_posts()) :
        $output = '<ul>';
        while ($subpages->have_posts()) : $subpages->the_post();
            $output .= '<li><strong><a href="'.get_permalink().'">'.get_the_title().'</a></strong>
                        <p>'.get_the_excerpt().'<br />
                        <a href="'.get_permalink().'">Continue Reading →</a></p></li>';
        endwhile;
        $output .= '</ul>';
    else :
        $output = '<p>No subpages found.</p>';
    endif;

    // reset the query
    wp_reset_postdata();

    // return something
    return $output;
}
add_shortcode('subpage_peek', 'subpage_peek');

/* Shortcode */

[subpage_peek]