Some Menu Items Not Working

This seems very strange to me. The menu on http://50.87.204.70 works correctly in Firefox. But in IE and Chrome they don’t. SPAWNnews and every item in the sub-menu are all Categories. But in IE and Chrome when I click on any of them, EXCEPT Indie Publishing or Business of Writing,it takes me to the homepage. I’m using a child theme of Twenty-Twelve, and I’ve ruled out that it’s not the CSS.