The Partner Sync Integration does not recognize parent/child relationships in Salesforce. It recognizes each record as its own account. This means you'll need to flag each account separately in Salesforce by choosing the appropriate value for the Account Type (or other picklist field) and checking the "Sync with Channeltivity" checkbox on the record. The system will then know to create the records in Channeltivity during the next sync. Once the sync runs, a Partner Organization will be created in Channeltivity for the parent account and another Partner Organization for the child account.

The contacts associated with each of the accounts will also be pulled into Channeltivity. When you are ready to promote the contacts to Users, the system will prompt you to associate the email domains to one of the following:

You'll select the Ignored Emails Domains option.