diff --git a/contrib/src/xrc/xh_sizer.cpp b/contrib/src/xrc/xh_sizer.cpp
index f26bac9e7a..eaeec961c2 100644
--- a/contrib/src/xrc/xh_sizer.cpp
+++ b/contrib/src/xrc/xh_sizer.cpp
@@ -142,6 +142,7 @@ wxObject *wxSizerXmlHandler::DoCreateResource()
 
         wxCHECK_MSG(m_parentSizer != NULL ||
                 (parentNode->GetType() == wxXML_ELEMENT_NODE &&
+                    m_parentAsWindow != NULL &&
                     (m_parentAsWindow->IsKindOf(CLASSINFO(wxPanel)) ||
                      m_parentAsWindow->IsKindOf(CLASSINFO(wxFrame)) ||
                      m_parentAsWindow->IsKindOf(CLASSINFO(wxDialog)))
diff --git a/src/xrc/xh_sizer.cpp b/src/xrc/xh_sizer.cpp
index f26bac9e7a..eaeec961c2 100644
--- a/src/xrc/xh_sizer.cpp
+++ b/src/xrc/xh_sizer.cpp
@@ -142,6 +142,7 @@ wxObject *wxSizerXmlHandler::DoCreateResource()
 
         wxCHECK_MSG(m_parentSizer != NULL ||
                 (parentNode->GetType() == wxXML_ELEMENT_NODE &&
+                    m_parentAsWindow != NULL &&
                     (m_parentAsWindow->IsKindOf(CLASSINFO(wxPanel)) ||
                      m_parentAsWindow->IsKindOf(CLASSINFO(wxFrame)) ||
                      m_parentAsWindow->IsKindOf(CLASSINFO(wxDialog)))