Every day, Seamus O’Malley goes down to the pub and orders three pints.
After a number of weeks, Mickey Flynn, the proprietor asks why the three pints.
Seamus explains that his brothers Patrick and Donald have moved to  Australia and  Canada but before they left, they promised each other that they would have a symbolic pint together each day. So each of them, heads to their local pub each day for their three pints for the three brothers.
This goes on for months.
One day, Seamus orders two pints. Mickey is a bit concerned by says nothing. Seamus orders two pints again the next day.
With a long face and a heavy heart, Mickey brings Seamus his two pints and tells Seamus that he is sorry for his loss.
Seamus is surprised by the message and asks Mickey to explain.
“You’re only ordering two pints. I assumed one of your brothers diedâ€, explained Mickey.
“Oh no. Sorry to worry you Mickeyâ€, replies Seamus, “it’s just that the doctor told me to give up drinkingâ€.
“But you’ve still ordered two pints†says Mickey, to which Seamus explains, “My brothers haven’t stopped drinking, only meâ€
Happy  St. Paddy’s Day