diff --git a/gtk/gtktooltipwindow.c b/gtk/gtktooltipwindow.c
index d4615647c7..28e63d095f 100644
--- a/gtk/gtktooltipwindow.c
+++ b/gtk/gtktooltipwindow.c
@@ -44,7 +44,7 @@
 
 struct _GtkTooltipWindow
 {
-  GtkWindow parent_type;
+  GtkWindow parent_instance;
 
   GdkSurface *surface;
   GskRenderer *renderer;