Fatal Error ! Please help

Dear All;

I would appreciate all your help and assistance here; i switched over to responsive theme and then i tried to update the WP version and thethem as advised on my dashboard. I now have no website and this is what i get on my website:

Warning: require(/home/laylakbrown/public_html/wp-content/themes/responsive/core/includes/functions.php): failed to open stream: No such file or directory in /home/laylakbrown/public_html/wp-content/themes/responsive/functions.php on line 17

Fatal error: require(): Failed opening required ‘/home/laylakbrown/public_html/wp-content/themes/responsive/core/includes/functions.php’ (include_path=’.:/usr/lib/php:/usr/local/lib/php’) in /home/laylakbrown/public_html/wp-content/themes/responsive/functions.php on line 17

Can you please help !

Thanks !