(WordPress) Page Layout with Dynamic Sidebar based on Parent Page

page.php

<?php 
/**
* Template Name: Page Layout
*/
get_header(); ?>

<div id="main" class="row"><div class="container">

	<?php 
		$children = get_pages('child_of='.$post->ID);
		$classes = get_body_class();

		if(count($children)!=0 || in_array('page-child',$classes) ) {
			$contentClass = ' style=""';
		} else {
			$contentClass = ' style="width:100%;"';
		} ?>


	<div class="main-content col-md-9 pull-right" <?php echo $contentClass ?>>

			<?php if (have_posts()) : ?>
			<?php while (have_posts()) : the_post(); ?>

			<h1><?php the_title(); ?></h1>

			<?php the_content(); ?>

			<?php endwhile; ?>	
			<?php else : ?>
			<?php endif; ?>

	</div>

	<?php
	if(count($children)!=0 || in_array('page-child',$classes) ) { 
		echo get_sidebar();
	}
	?>

</div></div> <!-- #main -->

<?php get_footer(); ?>

sidebar.php

<div class="sidebar col-md-3 pull-left widget-area" id="sidebar" role="complementary">
<h3>In this Section</h3>
	<?php /* Creates a menu for pages beneath the level of the current page */
		if (is_page() and ($notfound != '1')) {
		$current_page = $post->ID;
		while($current_page) {
		$page_query = $wpdb->get_row("SELECT ID, post_title, post_status, post_parent FROM $wpdb->posts WHERE ID = '$current_page'");
		$current_page = $page_query->post_parent;
		}
		$parent_id = $page_query->ID;
		$parent_title = $page_query->post_title;
		if ($wpdb->get_results("SELECT * FROM $wpdb->posts WHERE post_parent = '$parent_id' AND post_status != 'attachment'")) { ?>
		<ul>
		<!-- <?php ?>
		<li><a href="<?php echo get_permalink($parent_id); ?>"><?php echo $parent_title; ?></a></li>
		<?php ?> -->
		<?php wp_list_pages('sort_column=menu_order&title_li=&child_of='. $parent_id); ?>
		</ul>
	<?php } } ?>
</div><!-- end sidebar -->