diff --git a/gtk/gtkbbox.c b/gtk/gtkbbox.c
index 638959f740..b4348f1a66 100644
--- a/gtk/gtkbbox.c
+++ b/gtk/gtkbbox.c
@@ -56,6 +56,7 @@
 #include "gtktypebuiltins.h"
 #include "gtkprivate.h"
 #include "gtksizerequest.h"
+#include "gtkwidgetprivate.h"
 
 #include "gtkintl.h"
 
@@ -507,8 +508,8 @@ gtk_button_box_child_requisition (GtkWidget  *widget,
       if (gtk_widget_get_visible (child))
         {
           nchildren += 1;
-          gtk_widget_get_preferred_size_and_baseline (child,
-						      &child_requisition, NULL, &child_baseline, NULL);
+          _gtk_widget_get_preferred_size_and_baseline (child,
+                                                       &child_requisition, NULL, &child_baseline, NULL);
 	  if (orientation == GTK_ORIENTATION_HORIZONTAL &&
 	      gtk_widget_get_valign_with_baseline (child) == GTK_ALIGN_BASELINE &&
 	      child_baseline != -1)
@@ -552,8 +553,8 @@ gtk_button_box_child_requisition (GtkWidget  *widget,
           if (is_secondary)
             nsecondaries++;
 
-          gtk_widget_get_preferred_size_and_baseline (child,
-						      &child_requisition, NULL, &child_baseline, NULL);
+          _gtk_widget_get_preferred_size_and_baseline (child,
+                                                       &child_requisition, NULL, &child_baseline, NULL);
 
           if (homogeneous ||
               (!non_homogeneous && (child_requisition.width + ipad_w < avg_w * 1.5)))
diff --git a/gtk/gtksizerequest.c b/gtk/gtksizerequest.c
index ed30f9515d..3bdff2094e 100644
--- a/gtk/gtksizerequest.c
+++ b/gtk/gtksizerequest.c
@@ -646,8 +646,8 @@ gtk_widget_get_preferred_height_and_baseline_for_width (GtkWidget *widget,
 					    natural_baseline);
 }
 
-/**
- * gtk_widget_get_preferred_size_and_baseline:
+/*
+ * _gtk_widget_get_preferred_size_and_baseline:
  * @widget: a #GtkWidget instance
  * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
  * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
@@ -665,15 +665,13 @@ gtk_widget_get_preferred_height_and_baseline_for_width (GtkWidget *widget,
  * widget will generally be a smaller size than the minimum height, since the required
  * height for the natural width is generally smaller than the required height for
  * the minimum width.</para></note>
- *
- * Since: 3.10
  */
 void
-gtk_widget_get_preferred_size_and_baseline (GtkWidget      *widget,
-					    GtkRequisition *minimum_size,
-					    GtkRequisition *natural_size,
-					    gint           *minimum_baseline,
-					    gint           *natural_baseline)
+_gtk_widget_get_preferred_size_and_baseline (GtkWidget      *widget,
+                                             GtkRequisition *minimum_size,
+                                             GtkRequisition *natural_size,
+                                             gint           *minimum_baseline,
+                                             gint           *natural_baseline)
 {
   gint min_width, nat_width;
   gint min_height, nat_height;
@@ -747,8 +745,8 @@ gtk_widget_get_preferred_size (GtkWidget      *widget,
                                GtkRequisition *minimum_size,
                                GtkRequisition *natural_size)
 {
-  gtk_widget_get_preferred_size_and_baseline (widget, minimum_size, natural_size,
-					      NULL, NULL);
+  _gtk_widget_get_preferred_size_and_baseline (widget, minimum_size, natural_size,
+                                               NULL, NULL);
 }
 
 static gint
diff --git a/gtk/gtkwidget.h b/gtk/gtkwidget.h
index 25247d5701..49008cfba6 100644
--- a/gtk/gtkwidget.h
+++ b/gtk/gtkwidget.h
@@ -566,12 +566,6 @@ GDK_AVAILABLE_IN_ALL
 void                gtk_widget_get_preferred_size             (GtkWidget      *widget,
                                                                GtkRequisition *minimum_size,
                                                                GtkRequisition *natural_size);
-GDK_AVAILABLE_IN_3_10
-void                gtk_widget_get_preferred_size_and_baseline (GtkWidget      *widget,
-								GtkRequisition *minimum_size,
-								GtkRequisition *natural_size,
-								gint           *minimum_baseline,
-								gint           *natural_baseline);
 
 GDK_DEPRECATED_IN_3_0_FOR(gtk_widget_get_preferred_size)
 void       gtk_widget_get_child_requisition (GtkWidget         *widget,
diff --git a/gtk/gtkwidgetprivate.h b/gtk/gtkwidgetprivate.h
index 87943904ce..7f48a7c562 100644
--- a/gtk/gtkwidgetprivate.h
+++ b/gtk/gtkwidgetprivate.h
@@ -81,6 +81,11 @@ void _gtk_widget_get_preferred_size_for_size   (GtkWidget         *widget,
                                                 gint              *natural,
                                                 gint              *minimum_baseline,
                                                 gint              *natural_baseline);
+void _gtk_widget_get_preferred_size_and_baseline(GtkWidget        *widget,
+                                                GtkRequisition    *minimum_size,
+                                                GtkRequisition    *natural_size,
+                                                gint              *minimum_baseline,
+                                                gint              *natural_baseline);
 gboolean _gtk_widget_has_baseline_support (GtkWidget *widget);
 
 gboolean _gtk_widget_get_translation_to_window (GtkWidget      *widget,