People want to share emotional highs and lows with others. It's a big opportunity.
Thousands of people braved the cold to celebrate Obama's victory in Times Square. They could have stayed at home. At home they had chairs, alcohol and bathrooms. But they wanted to be with others on the same emotional plateau.
Your community is going to be happy, sad and angry about a lot of things. Each intense emotional state is an opportunity to invite outsiders to join your community. Find people that feel the same as your community and ask them to join.
You can find these outsiders by what they say on Twitter, via blogs, on Facebook, in comments on news stories and in related groups. Your cousin might even know people. You can ask your members to reach out to others who are on the same emotional high/low.
A shared emotional connection is a powerful factor in developing a sense of community.