diff --git a/src/common/sizer.cpp b/src/common/sizer.cpp
index 33c8d39ce1..ed956e4aea 100644
--- a/src/common/sizer.cpp
+++ b/src/common/sizer.cpp
@@ -869,7 +869,7 @@ bool wxSizer::Replace( wxSizer *oldsz, wxSizer *newsz, bool recursive )
 bool wxSizer::Replace( size_t old, wxSizerItem *newitem )
 {
     wxCHECK_MSG( old < m_children.GetCount(), false, wxT("Replace index is out of range") );
-    wxASSERT_MSG( newitem, wxT("Replacing with NULL item") );
+    wxCHECK_MSG( newitem, false, wxT("Replacing with NULL item") );
 
     wxSizerItemList::compatibility_iterator node = m_children.Item( old );