Your post reminds me of something an AP history teacher once told me. He tried to instill in us a duty to procreate. He told us that intelligent people need to outbreed to dumb people if we're ever going to get anywhere. So, if you're intelligent -- you must be to be thinking about such things -- and you've had children in which you've instilled the value of education and bettering oneself, then you've already made a difference.