diff --git a/src/generic/splitter.cpp b/src/generic/splitter.cpp
index df06c7d5e0..1573dd7a04 100644
--- a/src/generic/splitter.cpp
+++ b/src/generic/splitter.cpp
@@ -716,7 +716,7 @@ void wxSplitterWindow::Initialize(wxWindow *window)
     wxASSERT_MSG( (!window || (window && window->GetParent() == this)),
                   _T("windows in the splitter should have it as parent!") );
 
-    if (! window->IsShown())
+    if (window && !window->IsShown())
         window->Show();
 
     m_windowOne = window;