WORDPRESS: Retrieve children of a parent category - get_categories()

get_categories.php

<?php		
	/* Subcategories of "Journals" (id: 6) */
	$categories =  get_categories('child_of=6&hide_empty=0');
	foreach ($categories as $cat):
	
		 /* This get the total of posts in current category of the loop.*/
		$total_of_posts_in_category = (int) $cat->count;
		$current_category_name = $cat->name;
			
	   	/* For each category, make the loop for the amount of posts */
	   
	   	/* New wordpress query object - passing the arguments */
		$journals_query = new WP_Query('category_name='.$current_category_name.'&show_posts=-1&order_by=name&order=asc');
	
		/* This is the loop for the current category retrieved */
		while($journals_query->have_posts()):
		
			$journals_query->the_post();
			
			// [custom code...]
		endwhile;
	    
	endforeach;