Display posts exclusively in their category (not parent)

Hi all,

I am wanting to display posts in a child-category exclusively in the child category only. At the moment, by default, WordPress shows these posts in all parent categories as well…

Also, I am using the following snippet (below) to display child-categories on a parent page. Whilst it works, it displays the words “No categories” when there are no sub/child categories to display. So I was wondering if there was a better way to implement this, as I don’t want anything to appear if there are no child categories to show.

<?php
            $term = get_term_by( 'slug', get_query_var( 'term' ), get_query_var( 'taxonomy' ) );
            if ($term->parent == 0) { ?>
            <h2>Browse Sub-categories:</h2>
            <ul>
				<?php wp_list_categories('taxonomy=wpl_documents_category&depth=1&show_count=0
                &hide_empty=0&title_li=&child_of=' . $term->term_id); ?>
            </ul>
                <?php } else { ?>
            <h2>Browse Sub-categories:</h2>
            <ul>
                <?php
                wp_list_categories('taxonomy=wpl_documents_category&show_count=0
                &hide_empty=0&title_li=&child_of=' . $term->term_id);
                }
                ?>
            </ul>

Note: The above code shows multiple levels of child-category – so I need the updated code to do the same.

Any ideas/information on the above is greatly appreciated!

Thank you.