这就是我想到的。我不认为这是编写代码的理想方式，但它正是我所需要的。

通过排除父类别，我获得了侧栏中“相关项目”子类别部分的标签：

More in 
    <?php 
        $category = get_the_category();
        $catname = $category[0]->cat_name;
        if ($catname == \'News\' || $catname == \'Featured\' || $catname == \'Nav Bar News\') {
            $catname = $category[1]->cat_name;
                if ($catname == \'News\' || $catname == \'Featured\' || $catname == \'Nav Bar News\') {
                    $catname = $category[2]->cat_name;
                    if ($catname == \'News\' || $catname == \'Featured\' || $catname == \'Nav Bar News\') {
                        $catname = $category[3]->cat_name;
                    }
                }
            } else {
                $catname = $category[0]->cat_name;
            }
            echo $catname;
        ?>

这就是它变得有点凌乱的地方，但代码适用于我需要实现的目标。我排除了父类别，然后使用循环显示相关子类别中的帖子：

        wp_reset_query();
        $this_post = $post->ID;
        $category = get_the_category($post->ID);
        $category = $category[0]->cat_ID;
        if ($category == \'30\' || $category == \'28\' || $category == \'99\') {
            $category = $category[1]->cat_ID;
            if ($category == \'30\' || $category == \'28\' || $category == \'99\') {
                $category = $category[2]->cat_ID;
                if ($category == \'30\' || $category == \'28\' || $category == \'99\') {
                    $category = $category[3]->cat_ID;
                } 
            }
        } 
        $args = array(
            \'category__in\' => array($category),
            \'post__not_in\' => array($this_post)
        );
        $the_query = new WP_Query($args);

        if ( $the_query->have_posts() && !(in_category(\'32\'))) {
            $i = 0; while ( $the_query->have_posts() && $i < 1) {
                $the_query->the_post(); ?>
                        <?php the_post_thumbnail(\'medium\'); ?>
                        <a href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
                            <a href="<?php the_permalink(); ?>"><?php echo excerpt(30); ?></a>
                            <?php the_author(); ?>
            <?php $i++; } 
        } else {
            //echo \'no posts\';
        }
        wp_reset_postdata();

        wp_reset_query();
        $this_post = $post->ID;
        $category = get_the_category($post->ID);
        $category = $category[0]->cat_ID;
        if ($category == \'30\' || $category == \'28\' || $category == \'99\') {
            $category = $category[1]->cat_ID;
            if ($category == \'30\' || $category == \'28\' || $category == \'99\') {
                $category = $category[2]->cat_ID;
                if ($category == \'30\' || $category == \'28\' || $category == \'99\') {
                    $category = $category[3]->cat_ID;
                } 
            }
        } 
        $args = array(
            \'category__in\' => array($category),
            \'post__not_in\' => array($this_post),
            \'offset\' => 1
        );
        $the_query = new WP_Query($args);

        if ( $the_query->have_posts() && !(in_category(\'32\'))) {
            $i = 0; while ( $the_query->have_posts() && $i < 3) {
                $the_query->the_post(); ?>
                        <a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title(); ?>"><?php the_title(); ?></a>
                    <?php if ($i < 2) { ?>
                        <hr style="width: 92%;">
                    <?php } ?>
            <?php $i++; } 
        } else {
            //echo \'no posts\';
        }
        wp_reset_postdata();

我试图在一个循环中完成这一切，但我想不出一种方法来仅显示第一篇文章的特色图像，然后将该文章从再次显示中排除。如果有人有更干净的方式写这篇文章，请让我知道。