سلام
خوب شما کد زیر رو تست کن ببین وضعیت چطوره؟
<?php
$cat_obj = get_queried_object();
if($cat_obj->category_parent === 0) {
$childs_id = get_term_children($cat_obj->cat_ID, 'category');
if($childs_id !== array()) {
foreach($childs_id as $child_id) {
$wp = new WP_Query(array(
'post_type' => 'post',
'post_status' => 'publish',
'category__in' => $child_id,
'posts_per_page' => 5
));
if($wp->have_posts()) :
while($wp->have_posts()) :
$wp->the_post();
?>
<li>مطلب</li>
<?php
endwhile;
wp_