Getting Messages from Child's Child

My objects are setup like this:

Code:

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hFrame1 = CreateWindow("BUTTON", "Edit", WS_CHILD | WS_VISIBLE | BS_GROUPBOX | BS_NOTIFY, 10, 300, 740, 200, hWnd, (HMENU)R_Frame1, hInst, NULL);
hFrame2 = CreateWindow("BUTTON", "Layer:", WS_CHILD | WS_VISIBLE | BS_GROUPBOX | BS_NOTIFY, 10, 10, 160, 180, hFrame1, (HMENU)R_Frame2, hInst, NULL);
hButton1 = CreateWindow("BUTTON", "Add", WS_CHILD | WS_VISIBLE | BS_CENTER | BS_PUSHBUTTON | BS_VCENTER, 10, 160, 70, 18, hFrame2, (HMENU)R_Button1, hInst, NULL);

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Is there any way for my main form (hWnd) to get the BN_CLICKED message when hButton1 is clicked?

Group boxes have no childs. Create all 3 windows as direct childs of your main window then you have no problems. Why do you want this strange hierarchy?

If you really want to do it this way, you need to subclass the inner frame and forward the messages you want to the main window.