Without any statistical significance, but nonetheless the sample size is greater than 5. None of us consider their parents to be great, or even good teachers. All kids squandered sometime after they are free from the parents, usually in universities.
This experience impacts me so much, that I have a bias that teachers should not teach their own kids.
So I agree that yes, just having a parent who is a teacher doesn't necessarily get you much, outside of likely being in a home environment where school is deemed important (many don't have this unfortunately). But where things become slightly magical is when you have a genetically gifted child and a parent that both knows how to guide that genius and has the resources to do so.