And most modern parents would swamp the child with a bunch of mind rotting auto playing TV and video games. There's an account of Terence's time at university where he nearly fails his oral qualifying exams as he spent most of his time playing Civ rather than studying anything. Imagine the travesty for the world if 5 year old Terence had been handed an Xbox.
I think beyond even having supportive parents, the most important part was that he had a parent that had a degree in the field that he happened to be a genius in. His mother knew exactly how to guide her child through the material, even if it just was to let him go off to a corner and read the books she guided him towards for 3-4 hours a day for fun. So many children have advanced proclivities for certain things and parents that just can't even see what it is their child is brilliant at.
Having someone that knows the path and can point it out to them is a beautiful thing to have as a child.
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.
You also hear just the success stories which are often extremely marginal, when such approach wouldn't fit development curve of some other potential genius we would not be hearing their less successful story, would we.
Not diminishing the overall message, in 80s even in western democracies deeper info was not so readily available so its not like his parents just threw him wifi-connected tablet with wikipedia opened and that was it.
But I think what should be celebrated more is some proper hard long term effort and not just usual approach with exceptional results.
We are discussing his parent's contribution to his growth. Some, like me, tend to agree they just gave him (good) tools and he found his interest and way through and beyond due to superior analytical skills and overall intelligence, not through some super duper tutoring by them.
I have cca such cousin. He was way ahead of his class (which was already math-focused class from secondary school), geniune interest in deeper math, physics and philosophy from early age. Even very good at software development in old Pascal or C. Nobody was tutoring him in any way, he just went to public library and borrowed what he liked.
The stuff thats not hard but still counts as discovery and learning must be self-motivating in way more average folks simply don't experience, not with same topics.