Close Knit Sisterhood

Hi! I am not in Tri-Sigma but am in another sorority. I was just wondering how you guys maintain such strong sisterhood? I go to Winthrop University (Tri-Sigma is on our campus) and the Sigmas there seem to be such a tight knit group. Whenever you see one Sigma you see a huge group of Sigmas. They are never EVER apart. How do you guys maintain this? I wanted to incorporate such a magnitude of sisterhood into my chapter/sorority because we seem to splinter off into groups and leaving some out of the loop without a splintered off group.

Erica