Note: You must have Administrator privileges to edit member details on the Admin portal.
To begin the process login to the admin portal and select the Membership -> Current Members link from the menu.
Search for the payment email of the person who purchased the family membership.
From the Actions column select Edit.
You can now select the field of the existing members you wish to edit. If you want to remove a member select the "Remove Member" option below their information. If more members can be added you will see the "Add another Adult member" or "Add another Child member".