Can no longer access my site!

Hello All!

This is the link to my site livingleashless.com
I have a child theme that I was trying to add a post to a section using the php in the loop.
I entered this code:

<?php if ( cnr_have_children() ) : while ( cnr_have_children() ) : cnr_next_child(); ?>
<h3><?php the_title(); ?></h3>
<div><?php the_excerpt(); ?></div>
<?php endwhile; endif; ?>

and after hitting update was given this message on the screen:

Parse error: syntax error, unexpected ‘<‘ in /home/livin270/public_html/wp-content/themes/sydney-child/functions.php on line 21

I hit the back button, deleted the code, and hit update again, but to no avail I am still being given the same parse error message. Even when trying to get to the admin page through the back door by using livingleashless.com/wp-admin I was given the same message.

Please help! What do I have to do to get my site back.

Thank You!