diff --git a/lcl/forms.pp b/lcl/forms.pp
index ebcde8657b..5fd6b4a6a8 100644
--- a/lcl/forms.pp
+++ b/lcl/forms.pp
@@ -288,6 +288,7 @@ type
     property AutoScroll;
     property AutoSize;
     property BorderSpacing;
+    property ChildSizing;
     property ClientHeight;
     property ClientWidth;
     property Color nodefault;