I thought I knew what I was doing, but now I’m stumped.
The “Customers” table contains fields you would probably expect:
The “Add Ons” table contains these fields:
Customer ID (relationship established to “Customer ID” in “Customers” table
The end goal is to have a list layout that contains all fields from both tables. I actually have this running now. In the layout editor I dragged in the fields from “Customers”, then switched the field selector to related table “Add Ons”. There I dragged in the “Called Today” field.
If there is data in “Add Ons” that match records in “Customers” it displays just fine. However, if a record in “Customers” doesn’t have any related data in “Add Ons”, it doesn’t give them the ability to create that data from the list view by clicking into the field and typing in it.