My FI and I are planning a very small brunch wedding next May. I sent out "Save the Date" to family and very few friends that will be invited (30). Now we heard from MOG that FI's brother and wife that are invited are assuming that their grown sons and significant others are also invited. We don't have a relationship with them at all. I don't even know them. We only invited the real close family members and few friends. Do we have to invite them? I feel that we start going there, we will end up with 50 guest, way bigger wedding than we planned on...