OK, so because English was this guys second language, I was a little worried about him enjoying this joke. But in the end he laughed and all was well:

An Irish guy walks into the bar and orders three separate shots of whiskey. The Bartender finds this odd, but complies. He downs the shots, one two three and sits around for a bit, watches the game, chit chats and leaves.

The next day he comes back and does the same thing, three separate shots. The bartender decides to ask him why he ordered three separate shots and he replied: "Back in the old country, I left my two brothers, Patty and Seamus and every night I take a shot for myself and one for each of them."

The bartender found this to be a wonderful tradition and quickly befriended our Irishman. Years passed and every day the man came in and ordered the same thing, three shots...until one day he came in and ordered just two. The bartender became very worried. He asked if something had happened to one of his brothers and the Irishman simply replied "No no no, nothing like that...I just decided to quit drinking."