Ok, I know this'll sound cheesy, but we really are close. A lot of my sisters are best friends.
We all know each other and know random things about each other (like how tall our shortest sister is, etc.).
Of course we have socials and service, but I think our best quality is our love for each other. A great quality to be founded on!
(Yay Founders class!!! #8 here!)
ETA: We also have strong philanthropy - a national service project, a national philanthropy, a local service project, and a local philanthropy - but we help out with other projects too (ie, the Res Life staff asked us to help sell valentines to raise money for sickle cell anemia patients, so we helped with that
).