Can't view my posts in admin page

I have not updated my Version, because the last time I did, it screwed up my entire site and I had to back up my site.

I have updated some of my other plugins over the past month or 2, but not sure when this issue started. I just recently notices I can’t see my posts and get this error message.

<tr id="post-213" class="<br /> <b>Fatal error</b>: Call to undefined function _make_cat_compat() in <b>/home/content/02/10854302/html/wp-includes/category-template.php</b> on line <b>82</b><br />

I opened this file and sure enough the code does reference this function, but I did not write this code and the file states the last time it was updated was 8/26/2013 – so could an update to a plugin over write this .php file?

Code in file is:

function get_the_category( $id = false ) {
	$categories = get_the_terms( $id, 'category' );
	if ( ! $categories || is_wp_error( $categories ) )
		$categories = array();

	$categories = array_values( $categories );

	foreach ( array_keys( $categories ) as $key ) {
		_make_cat_compat( $categories[$key] );
	}

	// Filter name is plural because we return alot of categories (possibly more than #13237) not just one
	return apply_filters( 'get_the_categories', $categories );

My site is http://www.autobodyontherun.com

If anyone knows what I should do here, and how to update the code, it would be greatly appreciated.