$my_query = new WP_Query(‘cat=50′);
while ($my_query->have_posts()) : $my_query->the_post();$do_not_duplicate = $post->ID;
?>

 

$my_query = new WP_Query(‘cat=184′);
while ($my_query->have_posts()) : $my_query->the_post();$do_not_duplicate = $post->ID;
?>