Dorrian’s Red Hand, the casual restaurant/Irish pub run by the friendly, socially connected Upper East Side family The Dorrians, has been THE preppy hang out spot for decades. And this month, the Second Avenue hang out is turning 50! The clubby like bar is having a four day celebration. November 16th is “Alumni Karaoke Night,” the 17th is “80s Night” (toss back some G&Ts with people who remember when the drinking age was 18), the 18th is “90s Night” (when you could actually smoke cigs in a bar) and the 19th is “00′s Night” celebrating the new generation of boarding school bad boys and private school grad girls who flock nightly to what is now a New York landmark. Happy Birthday Dorrian’s. A big red handed high five!