Weird coincidence

Went out for Richards 30th last night and after the pubs closed we went to a club and there was this person standing next to me and she seemed really familiar and then I realised it was because she was my sister!
Which probably doesn't sound weird but we live in different cities, hadn't told each other we were going out in Edinburgh and in the ten years I've lived down here I've only gone out there three or four times!!!!