diff --git a/libs/canvas/box.cc b/libs/canvas/box.cc
index 1e1c246858..eaf39f931e 100644
--- a/libs/canvas/box.cc
+++ b/libs/canvas/box.cc
@@ -265,11 +265,11 @@ Box::add (Item* i)
 }
 
 void
-Box::child_changed ()
+Box::child_changed (bool bbox_changed)
 {
 	/* catch visibility and size changes */
 
-	Item::child_changed ();
+	Item::child_changed (bbox_changed);
 	reposition_children ();
 }
 
diff --git a/libs/canvas/canvas/box.h b/libs/canvas/canvas/box.h
index 3b0eb01441..fb2f01c3ec 100644
--- a/libs/canvas/canvas/box.h
+++ b/libs/canvas/canvas/box.h
@@ -75,7 +75,7 @@ public:
 	double top_padding, right_padding, bottom_padding, left_padding;
 	double top_margin, right_margin, bottom_margin, left_margin;
 
-	void child_changed ();
+	void child_changed (bool bbox_changed);
   private:
 	Rectangle *self;
 	bool collapse_on_hide;