Additional widget regions can get confusing for people if they aren’t using them. If you’re building a child theme for a client it’s a good idea to remove additional widget areas.

Here’s what the code looks like to register widgets in a theme framework:

 
//Code of the Framework to register 2 Sidebars 
function xtreme_register_dynamic_sidebars() { 
register_sidebar( array( 
'name' => 'Sidebar One',
'id' => 'sidebar-one',
'description' => 'Sidebar One',
'before_widget' => '<li id="%1$s" class="widget %2$s">',
'after_widget' => '</li>',
'before_title' => '<h5 class="widget-title">',
'after_title' => '</h5>' 
)); 
register_sidebar( array( 
'name' => 'Sidebar Two',
'id' => 'sidebar-two',
'description' => 'Sidebar Two',
'before_widget' => '  <li id="%1$s" class="widget %2$s">',
'after_widget' => '</li>',
'before_title' => '<h5 class="widget-title">',
'after_title' => '</h5>' 
)); 
do_action('childtheme_sidebars'); 
} 
add_action( 'widgets_init', 'xtreme_register_dynamic_sidebars' ); 

What we’re interested in is  do_action('childtheme_sidebars');

Add this to your child theme’s functions.php

 
//functions.php im Child-Theme
 
function xtreme_unregister_sidebar() { 
unregister_sidebar('sidebar-two'); 
} 
add_action( 'childtheme_sidebars', 'xtreme_unregister_sidebar' );