Cecilia: Trudy heard about our WhatsApp group. She wants to join.
Trevor: Why not?
Thomas: It's a family group and technically she's not family.
Trevor: Your understanding of family is very narrow... 
Thomas: For me family is either blood bonds or marriage
Trevor: And if you had an adopted child it wouldn't be your family then
Thomas: Trudy is not an adopted child. She's just a friend
Cecilia: Should we add her or not?
Trevor: Yes!
Thomas: No.
Thomas: We can make a different group if she wants to chat with us.
Thomas: But family group is just that
Cecilia: Maybe we should vote? 
Thomas doesn't want to add Trudy to their WhatsApp group because she doesn't belong to the family.