How to exclude child page on siblings and parent page?

I’m trying to hide details about a child page when I’m on the siblings and it’s parent page and I don’t know how.

What I made is exclude the child page details when I’m on it. I want to exclude the details that I’m geting about that page when I’m on it’s parent or siblings too.

Logic:

if current page is parent page, exclude children

if current page is not parent page, exclude children pages with meta value 1

Can anyone help me with this?

My code:

<?php 
$current_page_id = get_the_ID(); 

$args = array( 'post_type'=>'page',
               'meta_key' => 'show_info',
               'meta_value'=> 1,
               'exclude' => $current_page_id ); 

$pages = get_posts($args);

?>
<div class='custom_pages_container'>
  <h1 class="titlefade" style="font-size: 1.6em;">Usefull informations</h1>
  <?php foreach($pages as $page){ ?>
  <div class='custom_wrapp'>
    <div class='img_despre_bp'>
      <a target='blank' href='<?php echo get_permalink($page->ID); ?>'>
        <?php echo get_the_post_thumbnail($page->ID, 'homepage-thumb2'); ?></a>
    </div>
    <div class='despre_desc' style='text-align: left;'>
      <a target='blank' href='<?php echo get_permalink($page->ID); ?>'><h1 style="font-size: 1.6em;"><?php echo $page->post_title; ?></h1></a> 
    </div>
  </div>
  <?php } ?>
</div>