ファンインソン(いんくん)は男！嫁(奥さん)がいた！整形してるか調査

Fatal error: Uncaught TypeError: Unsupported operand types: string - string in /home/shinichiro/moyarin.com/public_html/wp-content/themes/the-sonic-child/functions.php:13 Stack trace: #0 /home/shinichiro/moyarin.com/public_html/wp-includes/shortcodes.php(355): birth1('day', '', 'birth') #1 [internal function]: do_shortcode_tag(Array) #2 /home/shinichiro/moyarin.com/public_html/wp-includes/shortcodes.php(227): preg_replace_callback('/\\[(\\[?)(birth|...', 'do_shortcode_ta...', '<p>\xE4\xBB\x8A\xE5\x9B\x9E\xE3\x80\x81\xE8\xA1\x9D...') #3 /home/shinichiro/moyarin.com/public_html/wp-includes/class-wp-hook.php(308): do_shortcode('<p>\xE4\xBB\x8A\xE5\x9B\x9E\xE3\x80\x81\xE8\xA1\x9D...') #4 /home/shinichiro/moyarin.com/public_html/wp-includes/plugin.php(205): WP_Hook->apply_filters('<p>\xE4\xBB\x8A\xE5\x9B\x9E\xE3\x80\x81\xE8\xA1\x9D...', Array) #5 /home/shinichiro/moyarin.com/public_html/wp-includes/post-template.php(255): apply_filters('the_content', '<p>\xE4\xBB\x8A\xE5\x9B\x9E\xE3\x80\x81\xE8\xA1\x9D...') #6 /home/shinichiro/moyarin.com/public_html/wp-content/themes/thesonic/single.php(36): the_content() #7 /home/shinichiro/moyarin.com/public_html/wp-includes/template-loader.php(106): include('/home/shinichir...') #8 /home/shinichiro/moyarin.com/public_html/wp-blog-header.php(19): require_once('/home/shinichir...') #9 /home/shinichiro/moyarin.com/public_html/index.php(17): require('/home/shinichir...') #10 {main} thrown in /home/shinichiro/moyarin.com/public_html/wp-content/themes/the-sonic-child/functions.php on line 13