PHP Code issue in Object Event Handler - Need help in Debugging

Summary

Taken a PHP script from Forums for updating child incidents by Updating Parent Incident

Content

HI ,

I am new to this forum. I need help on the issue with PHP script. As a part of POC I need to demonstrate Parent and Child Incident between incidents so if a parent Incident can be updated as solved the child incidents  should get updated.  I have taken the script from a forum and applied it as per the given guidelines. But I am not able to update child incidents as per the logic specified. Please let me know how to debug and find where the issue is.