我禁用了父框，以避免父框向左移动。

add_action( \'admin_footer-post.php\',     \'wpse_98274_disable_top_categories_checkboxes\' );
add_action( \'admin_footer-post-new.php\', \'wpse_98274_disable_top_categories_checkboxes\' );

/**
 * Disable parent checkboxes in Post Editor.
 */
function wpse_98274_disable_top_categories_checkboxes() {
    global $post_type;

    if ( \'post\' != $post_type )
        return;
    ?>
        <script type="text/javascript">
            jQuery( "#category-all ul.children" ).each( function() {
                jQuery(this).closest( "ul" ).parent().children().children( "input" ).attr( \'disabled\', \'disabled\' )
            });
        </script>
    <?php
}

add_filter( \'wp_terms_checklist_args\', \'wpse_98274_checklist_args\' );

/**
 * Remove horrid feature that places checked categories on top.
 */
function wpse_98274_checklist_args( $args ) {

    $args[\'checked_ontop\'] = false;
    return $args;
}