Each contact, may have related contacts that you want to record, but not create a separate contact.
Do to do this. Open the Contact that you wish to add more contacts to.
Open Contact persons by selecting the pencil mark or click to edit:
This will open a list of contacts added to this particular contact.
Select + Add contact person
This will open a contact details form:
You can select a relation to main contact from the drop down, convenient for knowing the relationship.
Record the following information for a related contact person
You can add many related contacts, these will be listed in the main Contacts details window