Right Sidebar – widgets move

When I try to put another widget into my right sidebar, the widget moves to below my page. There's plently of available space in the sidebar, so I don't know why this is happening. Here is an example: http://bthreviews.com/bloodstone-review/ "Our Rating Scale" should be in the sidebar, not below the comment section. I thought it might have been because the text wasn't wrapping or something, so I tried an image instead, and it did the same thing.