sidebar dropped below content

The sidebar on this website – http://stephaniejoanne.com/

randomly dropped to below the posts on the homepage, on the other pages the side bar is fine. so i’m guessing its some coding on the home page that magically changed. The client said all they did was add a new post and it moved down. so who knows what happened. i deleted the post but its still below. I checked the main page index file for any open or unclosed div tags but couldnt find any.

anyone have any suggestions?