Yes, that's right - I'm asking about older children!
We already know that we're inviting the infants of out-of-town relatives who would not be able to attend if we did not invite their children. However, there are some relatives who live around an hour away from our venue who have children in their teens that we would prefer not to invite, because they're cousins' children. I have an absolutely massive extended family - I'm talking almost a hundred people - and I need to limit the number of family members I invite or it will be terribly imbalanced between my side and my fiance's side. Is there a proper way and time to communicate to my extended family members (my parents will be glad to help, too) that, unfortunately, we can't include their teenage children (who I don't know terribly well)? But that we're inviting out-of-town infants (and friends' kids)?