diff --git a/lcl/interfaces/gtk3/gtk3widgets.pas b/lcl/interfaces/gtk3/gtk3widgets.pas
index b9623f4c81..d23b2edae7 100644
--- a/lcl/interfaces/gtk3/gtk3widgets.pas
+++ b/lcl/interfaces/gtk3/gtk3widgets.pas
@@ -408,7 +408,6 @@ type
     procedure SetVisible(AValue: Boolean); override;
   public
     procedure InitializeWidget; override;
-    procedure AddChild(AWidget: PGtkWidget; const ALeft, ATop: Integer); virtual;
   end;
 
   { TGtk3Page }
@@ -4921,14 +4920,6 @@ begin
   end;
 end;
 
-procedure TGtk3Container.AddChild(AWidget: PGtkWidget; const ALeft, ATop: Integer);
-begin
-  if Assigned(FCentralWidget) then
-    PGtkFixed(PGtkScrolledWindow(FCentralWidget)^.get_child)^.put(AWidget, ALeft, ATop)
-  else
-    PGtkContainer(Widget)^.add(AWidget);
-end;
-
 { TGtk3ToolBar }
 
 procedure TGtk3ToolBar.ClearGlyphs;