AWS SDK for .NET Documentation
Cause Property
AmazonAmazon.SimpleWorkflow.ModelWorkflowExecutionCancelRequestedEventAttributesCause Did this page help you?   Yes   No    Tell us about it...
If set, indicates that the request to cancel the workflow execution was automatically generated, and specifies the cause. This happens if the parent workflow execution times out or is terminated, and the child policy is set to cancel child executions.

Constraints:

Allowed Values
CHILD_POLICY_APPLIED

Declaration Syntax
C#
public string Cause { get; set; }

Assembly: AWSSDK (Module: AWSSDK) Version: 1.5.60.0 (1.5.60.0)