Widgets act different in IE and Firefox

I am totally new to WordPress. I have created two simple sites using two plug ins.

Here is my problem.

In https://retreats.cpcbarn.org
I have a Primary and Secondary Widget Area. They are identical on all pages. I am using the Twenty 10 theme.

The problem is that one page (the Deus Solus page) does not display either the Primary or Secondary Widget in IE but does in Chrome and Firefox.

I don’t know if this is a bug in the Theme or in the basic handling of Widgets or something I did. It smells a lot like a bug in WordPress.

I just want to resolve the issue.