get details of data in subgrid in CRM word template

I have an entity named Medical Case

Each MedicalCase contains a subgrid of Families 

Each Families will have three lookup fields(Father,Mother,Child) to contacts

In the CRM Word tempalte, I am able to add a repeater for Families and get the contact names(3 look ups)

Now I also want to get the phone number field of the Contacts in the Families that are in the subgrid

How can i do that?