Fatal Error – child theme

Using Sydney theme – site was up and running just fine. I was trying to set up Woocommerce and make the shop page full width but I couldn’t edit the functions.php so I read that I could do this with a child theme. My page is already customized at the parent level. I installed the child theme and then page wouldn’t load. Went back to parent theme and now I get this:

Fatal error: Uncaught Error: Call to undefined function sydney_slider_template() in /home2/joelwood/public_html/tpowband.com/wp-content/themes/sydney/header.php:60 Stack trace: #0 /home2/joelwood/public_html/tpowband.com/wp-includes/template.php(688): require_once() #1 /home2/joelwood/public_html/tpowband.com/wp-includes/template.php(647): load_template(‘/home2/joelwood…’, true) #2 /home2/joelwood/public_html/tpowband.com/wp-includes/general-template.php(41): locate_template(Array, true) #3 /home2/joelwood/public_html/tpowband.com/wp-content/themes/sydney/page-templates/page_front-page.php(6): get_header() #4 /home2/joelwood/public_html/tpowband.com/wp-includes/template-loader.php(74): include(‘/home2/joelwood…’) #5 /home2/joelwood/public_html/tpowband.com/wp-blog-header.php(19): require_once(‘/home2/joelwood…’) #6 /home2/joelwood/public_html/tpowband.com/index.php(17): require(‘/home2/joelwood…’) #7 {main} thrown in /home2/joelwood/public_html/tpowband.com/wp-content/themes/sydney/header.php on line 60

Any help would be greatly appreciated. I’d even be fine without having the shop full width if I could just get my site back up to where it was. My backup service isn’t running because I have “too many inodes” – I’m guessing because of years of email? Anyway, thanks in advance.

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