>>150324153 (OP)
Talent appears and disappears from generation to generation in an unpredictable manner. So it's comparatively common for the kid of a pro athlete to be less talented than the father. But the kid usually has an interest in said sport because of the father, and the father's wealth and status allows the kid to receive elite training and nutrition and so on. That usually means the kid is better than most other kids - and has good contacts as well as a big name, things that come in handy when searching a club
Even if a kid is as talented as the father, their problem often is a lack of drive: your dad has earned millions, your family is set for life. You don't have to make it as an athlete yourself, you can lean back in any case. And deep down, they often don't want to be compared with their father. All of that isn't really helpful when it comes to putting in the work required to become one of the best 1% among the best 1%