First off, I'm using the win32 api. Now here is the problem, I want to have a multiline edit box control another multiline edit box when a its vertical scroll bar is moved. I know that edit boxes don't send a message to the parents WM_VSCROLL. I only get the edit controls EN_VSCROLL message from the WM_COMMAND message when a scroll bar's arrows are pressed or when a you move the scrollbar by not using its thumb. Any suggestions?