diff --git a/gdk/gdkinternals.h b/gdk/gdkinternals.h
index e35d9392db..973838087c 100644
--- a/gdk/gdkinternals.h
+++ b/gdk/gdkinternals.h
@@ -630,6 +630,8 @@ GdkEvent * _gdk_make_event (GdkWindow    *window,
 			    GdkEventType  type,
 			    GdkEvent     *event_in_queue,
 			    gboolean      before_event);
+gboolean _gdk_window_event_parent_of (GdkWindow *parent,
+                                      GdkWindow *child);
 
 void _gdk_synthesize_crossing_events (GdkDisplay                 *display,
 				      GdkWindow                  *src,
diff --git a/gdk/gdkprivate.h b/gdk/gdkprivate.h
index e35f30c2bf..031fe9ae7f 100644
--- a/gdk/gdkprivate.h
+++ b/gdk/gdkprivate.h
@@ -43,9 +43,6 @@ void gdk_synthesize_window_state (GdkWindow     *window,
                                   GdkWindowState unset_flags,
                                   GdkWindowState set_flags);
 
-gboolean _gdk_window_event_parent_of (GdkWindow *parent,
-                                      GdkWindow *child);
-
 /* Tests whether a pair of x,y may cause overflows when converted to Pango
  * units (multiplied by PANGO_SCALE).  We don't allow the entire range, leave
  * some space for additions afterwards, to be safe...