|One gay Czech, quite famous|
4% is the said proportion of gays in the Czech Republic. Let's say 5% to simplify the maths. Given the fact that there are 10 mill people in Cz, the math is fairly straightforward anyway. For every homosexual there are two parents of homosexuals.
2 x 5% of 10 mill = 1 million.
Of course there will be some variation as two gay people might come from the same family, some parents will have died and other mitigating factors, but let us say that there are 1 million parents of gays plus half a million gays, and if we move up to grandparents ....
Where do we go with these numbers?