How to remove these certain objects from my site design?

Hi,

You'd think I would know how to do this by now, but I can't seem to get it right. If you examine my test site, testadmin.citiera.com, you can see an Ad and the users username, date, and comments off. I found that the div classes for it are article-meta and then article-body, and I changed the CSS properties to display:none; but it still displays. This is a child theme, and I have about 6 child themes that need the same done on each. There is the parent theme installed. Do I make the changes on the child themes or on the parent theme?