Child Incident state is not moving from new to in-progress when parent incident state changed to In-Progress.Issue When a parent incident is moved to In Progress the child incident associated is not moving to 'In progress ' state. The sync between parent and Child is not working. Release All Cause Parent and child incident state synchronization is controlled by the business rule “Sync Child Incident State.” This rule is delivered with the Incident Management Best Practice plugin (for example, com.snc.best_practice.incident.kingston in older releases). If the plugin is not installed, or the business rule is inactive or its conditions do not match the states involved, the child incidents are not updated. Resolution The parent and child Incident state synchronization is controlled by the business rule " Sync Child Incident State ', refer the below documentation which explains the samehttps://docs.servicenow.com/csh?topicname=c_IncidentManagement.html&version=latestThis Business rule comes as part of the plugin ' Incident Management Best Practice - Kingston plugin (com.snc.best_practice.incident.kingston) 'If you do not have this plugin activated the parent-child incident state sync does not work because of the missing business rule which controls the synchronizationThis sync between parent and child works for the states as described in the below doc :https://docs.servicenow.com/csh?topicname=parent-child-state-sync.html&version=latestIf you do not want to install the plugin, they need to customization the synchronization to work and write business rule based on the requirement Related Links STEPS TO REPRODUCE: Login to the affected instanceOpen an Incident which has child incidents associatedChange the Parent incident state from New to In progressThe child incident state is still in new and is not moving to 'In progress '