diff --git a/app/models/communication/block/heading.rb b/app/models/communication/block/heading.rb
index bdb9685db4ea6b8be4af76fd0e60d378aa96d610..8728e33a50bdeb168d52e6b583fe788be24ef6e3 100644
--- a/app/models/communication/block/heading.rb
+++ b/app/models/communication/block/heading.rb
@@ -39,7 +39,8 @@ class Communication::Block::Heading < ApplicationRecord
               optional: true
   has_many    :children,
               class_name: 'Communication::Block::Heading',
-              foreign_key: :parent_id
+              foreign_key: :parent_id,
+              dependent: :nullify
   has_many    :blocks,
               dependent: :nullify