如何获取当前自定义帖子的子帖子并按自定义字段编号进行排序？

I have custom post type 'cars' and its child post type is 'carvariants'.

What I want to do is get child posts (carvariants) of current post (cars). I tried this code:

    <div>
    <?php 
    $parent_id = 1064;
    $the_query = new WP_Query(array(
'post_parent' => $parent_id,
        'post_type'         => 'carvariants',
        'posts_per_page'    => 1,
        'meta_key'          => 'wpcf-minimum-price',
        'orderby'           => 'meta_value_num',
        'order'             => 'ASC'
    ));

    ?>
    <?php if( $the_query->have_posts() ): ?>
        <ul>
        <?php while( $the_query->have_posts() ) : $the_query->the_post(); 
                $compprd = get_the_ID(); ?>

  <?php the_title(); ?>
     <?php
         endwhile; ?>
        </ul>
    <?php endif; ?>
    <?php wp_reset_query();  ?>
    </div>

I want to display child posts of Cars order by custom field wpcf-minimum-price but 'post_parent' is not working. This code is showing blank output. Whats wrong in this?

I didn't try this. But I hope this will work.

If it will not work, leave me a comment, and I will try to make it work.

Also, if there are better solutions, I will be glad to see the code from professionals:

<div>
    <?php 
    $parent_id = 1064;
    $args = array( 'child_of' => $parent_id );

    $children_pages = get_pages( $args );

    if ( count( $children_pages ) != 0 ) :
        foreach ( $children_pages as $children_page ) :
            if ( $children_page->have_posts() ) :
                    $args_for_posts = array( 'posts_per_page' => 1,
                        'post_type' => 'carvariants',
                        'orderby' => 'meta_value_num',
                        'order' => 'ASC',
                        'post_parent' => $children_page );
                    $postlist = get_posts( $args_for_posts );
                    foreach ( $postlist as $post) :
                        setup_postdata( $post ); ?>
                        <ul>
                            <?php
                            the_post();
                            ?>
                        </ul>    
                    <?php
                    endforeach;
                    wp_reset_postdata();
            endif;
        endforeach;
    else : ?>
        <p>No content to show.</p>
    <?php 
    endif; ?>
</div>