Having over 200 members I can understand why not everyone would no all of their sisters. Just like any other sorority you won't know everyone, which is fine. It is a respect that is given when you see another girl in her letters that you still go up say hello, etc. They also make every effort to incorporate the new members and make them feel welcome. My roommate said her first 2 weeks in she has hundreds of friend requests, follows, text messages, and invites to hang out.