Disabling left splitter for docking pane

We are displaying multiple components in several docking panes in a single window.  These panes should all be able to be resized. 
Original Display:


The issue we've come across is that there is a splitter on the left side of the window that allows an empty pane to be displayed, which we do not want. 


Is there a way to remove this splitter, but still allow all other splitters in the window to work?  

Thank you so much.  That worked.  I knew there was probably something very easy that I was missing.