I have a custom field on a category where you can add an image. I have it as a background image to show on the category's archive page, like so:
<body style="background:url('<?php echo z_taxonomy_image_url($cat->term_id); ?>')">
It uses the Categories Images plugin to achieve this.
Is there a way for the posts in this parent category to inherit this background image? something like $cat->parent_id?