I created a dialog with a child control, child control has it's own thread and message pump, and it has the dialog window set as the parent.
Is this a bad idea?

I already noticed I cannot wait on the window creation from the main dialog thread, because when the child thread calls CreateWindowEx with my dialog hwnd as the parent, it must invoke the main dialogs message loop, because I get deadlock.
As long as I don't do that, everything seems to work ok.
Do child windows post or send messages to their parents which could potentially cause me more deadlocks? (If I am going to use sendmessage to contact my child control this could cause problems)