Vincent has grey hair, a pot belly, and is one of the more annoying old gamblers/ railbirds at the local pool room. He does something slick and possibly shady but with easier hours as a day job- loan collector, repo man, used car salesman, book maker... One day a young man walks in and introduces himself as his son, that Vincent never knew he had.
Kid is in trouble and going nowhere in life. He needs his dad's help on a very immediate issue, and while solving that, long term Vincent decides to try to teach the kid all of the lessons he wished he'd learned earlier on. In return, the kid knocks some of the irritating shortsightedness out of old Vincent.
That's all I've got- I'm trying to continue the story and leave room for the next generation, too.