page.php

<?php
get_header();
while (have_posts()) {
    the_post(); ?>

    <?php page_banner(); ?>

    <div class="container container--narrow page-section">
        <?php
        $parent_id = wp_get_post_parent_id(get_the_ID());
        if ($parent_id != 0) {
        ?>
            <div class="metabox metabox--position-up metabox--with-home-link">
                <p>
                    <a class="metabox__blog-home-link" href="<?php echo get_permalink($parent_id) ?>"><i class="fa fa-home" aria-hidden="true"></i>Back to <?php echo get_the_title($parent_id); ?></a> <span class="metabox__main"><?php the_title(); ?></span>
                </p>
            </div>

        <?php
        }
        ?>


        <?php
        $test_array = get_pages(array(
            'child_of' => get_the_ID()
        ));

        if ($parent_id || $test_array) { ?>

            <div class="page-links">
                <h2 class="page-links__title"><a href="<?php echo get_permalink($parent_id); ?>"><?php echo get_the_title($parent_id); ?></a></h2>
                <ul class="min-list">
                    <?php
                    if ($parent_id != 0) {
                        $find_children_of = $parent_id;
                    } else {
                        $find_children_of = get_the_ID();
                    }
                    wp_list_pages(array(
                        'title_li' => NULL,
                        'child_of' => $find_children_of,
                        'sort_column' => 'menu_order'
                    )) ?>
                </ul>
            </div>

            <div class="generic-content">
                <?php the_content(); ?>
            </div>
    </div>
<?php } ?>

<?php
}
get_footer();
?>