Represents a client that is related to the main client.
When using this to add or update a relationship:
- If ClientCode is specified, the existing client with that code is used in the relationship. If updating the relationship, and the ClientCode is changed, the client used on the relationship is changed. Additionally, if any of the other details are not blank, that existing client is updated with the new details.
- If ClientCode is not specified, the other details are used to create a new client. In this case, Surname is mandatory, GivenName should be specified if it is not a single-name client, and at least one of Email, MobilePhone or HomePhone is mandatory.
