Responsive child theme function-sidebar.php

I am using Responsive theme and created a child theme too where I edit my files. I’d like to add some custom sidebars to custom templates. I learned I can use register sidebar function with array and add that to my template page. If I add this function under function-sidebar.php in mother theme, it shows under widget sections but when I put the <?php if ( !dynamic_sidebar( ‘custom-sidebar’ ) ) : ?> in the template in child theme the front site breaks.
Also when I add the function to function-sidebar.php in child theme, nothing happens.

Another question: when I add function.php in the main directory to my child theme the whole site breaks. I thought I can include any files from mother theme into child theme.

Any suggestions please?
Thanks