Explanation: `Related Events’ displays the AWS CloudTrail event ID that is related to the change that triggered the creation of the CI. There is a new CI made for every change made against a resource. As a result a different CloudTrail event IDs will be created. This allows you you to deep-dive into who or what and when made the change that triggered this CI. A great feature allowing for some great analysis to be taken, specifically when this affects security resources.
Reference: http://docs.aws.amazon.com/config/latest/developerguide/resource-config-reference.html#config-item-table