An Irishman named O'Malley went to his doctor after a long illness.
The doctor sighed and looked O'Malley in the eye and said, "I've some bad news for you. You have cancer, and it can't be cured. You'd best put your affairs in order."
O'Malley was shocked, but being a solid character, he managed to compose himself and walk from the doctor's office into the waiting room, where his son was waiting.
"Well, Son," O'Malley said, "We Irish celebrate when things are good, and we celebrate when things don't go well. In this case, things aren't so well. I have cancer. Let's head to the pub and have a few pints."
After 3 or 4 pints the two were feeling a little less somber. There were some laughs and some more beers. They were eventually approached by some of O'Malley's friends who were curious as to what the two were celebrating.
O'Malley told them they were drinking to his impending end. He told his friends, "I have been diagnosed with AIDS." The friends gave O'Malley their condolences, and they had a couple of more beers.
After the friends left, O'Malley's son leaned over and whispered his confusion. "Dad, I thought you told me that you were dying of cancer, but you just told your friends that you were dying of AIDS!"
"It's like this, m'boy," O'Malley said. "I don't want any of them bastards sleeping with your mother after I am gone."