diff --git a/src/common/sizer.cpp b/src/common/sizer.cpp
index 37f31766a3..1fd2b74d71 100644
--- a/src/common/sizer.cpp
+++ b/src/common/sizer.cpp
@@ -976,6 +976,8 @@ void wxSizer::Layout()
     CalcMin();
 
     // Applies the layout and repositions/resizes the items
+    wxWindow::ChildrenRepositioningGuard repositionGuard(m_containingWindow);
+
     RecalcSizes();
 }
 
diff --git a/src/common/wincmn.cpp b/src/common/wincmn.cpp
index 1601d08e42..3c2c0f4e1d 100644
--- a/src/common/wincmn.cpp
+++ b/src/common/wincmn.cpp
@@ -2610,6 +2610,8 @@ void wxWindowBase::SetConstraintSizes(bool recurse)
     wxLayoutConstraints *constr = GetConstraints();
     if ( constr && constr->AreSatisfied() )
     {
+        ChildrenRepositioningGuard repositionGuard(this);
+
         int x = constr->left.GetValue();
         int y = constr->top.GetValue();
         int w = constr->width.GetValue();