Ladies how do break the news the whole family isn't invited?

This is a good phrase to use for a variety of things that will come up for you: "I'm sorry, because of space and financial restraints, we weren't able to invite the kids. Hope you understand." That same phrase can be adapted and used in a variety of situations that might come up for you, such as a friend that didn't get invited. Keep in mind that a few people will be inconsiderate and bring their kids anyway, but just let it go.