Added new sidbar. Random div appears above widgets?

Hi all,

I have added a side bar and widget area to my site. Alls fine, but a random div with a height appears about my widgets. So, in element inspector it looks like this:

<div id="blogsidebar">
   <ul>
      <div style="height: 280px;"></div>
      <li>WIDGET HERE</li>
  </u>
</div>

I’ve checked and there’s no random JQuery adding this. I have also checked with a few different widgets.

My sidebar-blog.php just looks like:

<div id="blogsidebar">
   <ul>
      <?php
      if ( !function_exists('dynamic_sidebar') || !dynamic_sidebar('blog-sidebar') ) :
      endif; ?>
   </ul>
</div>

Would anyone know why this is occurring?

Thanks!