Display Child Page title and Image In WordPress

<?php
$child_pages = $wpdb->get_results(“SELECT *    FROM $wpdb->posts WHERE post_parent = “.$post->ID.”    AND post_type = ‘page’ ORDER BY menu_order”, ‘OBJECT’);  ?>
<?php if ( $child_pages ) : foreach ( $child_pages as $pageChild ) : setup_postdata( $pageChild );
$i+=count($pageChild); ?>

<a href=”<?php echo  get_permalink($pageChild->ID); ?>” rel=”bookmark” title=”<?php echo $pageChild->post_title; ?>”> <?php echo get_the_post_thumbnail($pageChild->ID, ‘full’); ?></a><br/>
<h3><a href=”<?php echo  get_permalink($pageChild->ID); ?>” rel=”bookmark” title=”<?php echo $pageChild->post_title; ?>”><?php echo $pageChild->post_title; ?></a></h3>

<?php endforeach; endif; ?>