A WordPress plugin to inherit the featured image of the Post / Page parent, grand-parent, etc.
If no featured image has been defined for a post / page / custom post type, then the plugin assigns a featured image from the parent, grand-parent, etc. To override the inherited featured image, simply use the 'Add Media' button and its 'Set Featured Image' feature.
The plugin hooks into the 'get_post_metadata' WordPress filter, so featured images are assigned dynamically -- disable the plugin to remove the dynamically assigned featured images. The plugin also uses the WordPress
update_meta_cache() functions to integrate fully with core WordPress functionality.