Example with mandatory variables not filled in

---                                                                             
family1:                      # The first family                                
  var: example                                                                  
family2:                      # The second family                               
  var: example                                                                  

Example with all variables modifiable

---                                                                             
family1:                      # The first family                                
  var: example                                                                  
family2:                      # The second family                               
  var: example