Weird Date Div Appearing Below Posts

Hi all. I’m playing around with the CSS, and I’ve noticed that when I wrap a border around the date, a small box appears above posts on that same day. It looks as though WP is suppressing the date when multiple posts are made on the same day, but I don’t see the call for it in the template. Here’s a link to the page so you can see what I’m talking about:
https://scott.littlemeanfish.com/wp/index3.php
Scroll down to 6/11, where there were two posts in one day to see what I mean.
Any help getting rid of that empty div?
Thanks in advance.
Cheers
Scott