Editable Grid with one to many relationships

I have my own data or CDT called "Clients" and i have a relationship with other CDT called "Vendor"

I have this editable grid created with the CDT called "Clients" (red square image bellow) this works great.

Now i want add the related data or relationship of the CDT called "Vendor" (blue square image bellow) into the editable grid 

Its possible?

How do I call that data?, what expression should I use?

Here is my relationships between my data 

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