Monochrome HELP! Issue with archives / categories

Wondering if anyone can help me crack my problem with the archives / categories of the Monochrome template…..

I’ve set up a site @ lauraenelson.com and things are flowing smoothly EXCEPT when you select from a tag or category on the right side to navigate…. then the archived posts show up as they should, but the right sidebar gets pushed to the bottom.

Example of this problem here: http://lauraenelson.com/archives/tag/articles

There are no differences within the code of the ride sidebar between pages, so there is something else forcing that to the next line… but not quite sure where. Am at my wit’s end, have no idea how to resolve this!

Thanks in advance if something comes to mind! 🙂