I posted this in another thread, but I'm a proud sorority-aunt, so I'll post again.
We had a twin go through rush and pledge ASA. Her twin sister COBed the next week. The twin that went through rush just had a little baby legacy last week.
They were honestly two of my favorite sisters, and the ones I keep in contact with the most to this day.
ETA: Also, AlwaysSAI and AlwaysAlphaGam are twins...and you can guess how that turned out by their usernames.