Bisexual Son

Four men go out to play golf. One is detained in the clubhouse and the remaining three are discussing their children while walking to the first tee.
 
"My son," says one, "Has made quite a name for himself in the home-building industry. He began as a carpenter, but now owns his own design and construction firm. He's so successful that in his last year he was able to give a good friend a brand new home as a gift."
 
The second man, not to be outdone, tells how his daughter began her career as a car salesperson, but now owns a multi-line dealership. "She's so successful, in fact, in the last six months she gave a friend two brand new cars as a gift."
 
The third man's says "My son has worked his way up through a stock brokerage firm, and in the last few weeks, has given a good friend a large stock portfolio as a gift."

As the fourth man arrives, they tell him that they have been discussing their children and ask him about his son. "To tell the truth, I'm not very pleased with how my son has turned out," he replies. "For fifteen years, he's been in and out of work and I've just recently discovered he's a bisexual. But, on the bright side, he must be good at what he does because his last three lovers have given him a brand new house, two cars, and a big pile of stock certificates."