I think your mother may be right - but I think her percentage is a little high. I'd say about 60% is genetic and 40% is parental, environmental, situational. I've lived all my life believing the opposite was true - that how you were raised is responsible for how you "turn out". But I believe everyone has a certain "temperment" and that coupled with how/where they are raised will determine how they "turn out". I believe this because if you look at a group of siblings - who have gone through some sort of trauma in their life - they all won't "turn out" the same. Some kids will seem to be destroyed by it - and have problems with depression, and anxiety. another one may become very angry and put up a wall and another may completely overcome it and lead a normal healthy life. Why is that? I think it is all temperment - or the ability to cope based on your personality type. Some people are shy and timid and sensitive - and so their experiences (especially negative ones) are MAGNIFIED to them and it seems to hurt them more - they internalize everything. Other people are extroverted and strong and have a thick skin - so negative experiences can kind of roll off their back easier.
I think your mom is dead on, and actually it's been shown in studies that siblings influence the behavior/life of each other much more than parents do.
I majored in sociology in the late 1970's, and it was all about the "clean slate theory" - that is, humans arrived in the world as a "clean slate" and are a product of all the influences around them. How misguided! All you have to do is have kids, and you can see they basically come like they come.
It appears sometimes that parents have great influence over their kids - that parents who demand neatness get neatness, parents who are into social graces have socially graceful kids - but I think most of that is genetic. ;D They pass on their basic personalities.
Parents whose lives are chaos, and they are HORRIBLE parents often have kids who are completely messed up and unsuccessful - but I think that's because they were dealt a hand of cards that includes personality disorders.
Twins, separated at birth, are very interesting. Amazing, really, how they turn out the same even though they are raised completely differently.
I do not know the percentages either, but I agree with your mother. I am a retired teacher and it was eye-opening to teach the second generation. Most of the children looked like their parent, acted like their parent, learned like their parent and thought like their parent. It was so weird to see the little things repeating themselves as how they sat in the desk, or being kind or unkind, or even signing their name. The good part is that even though parents do not have that much influence, neither do peers. I believe most of the personality/temperament and even values are innate.
We have two sons - one is like his maternal grandfather; the other is like his paternal grandfather. These two men are miles apart in personality, temperament and values. My husband and I are not like either one of our fathers and yet our sons each mimic one of their grandfathers. And no, neither was particularly close to either grandfather. Genetics - mostly genetics.
What a perspective, jdtm, to have taught two generations. I completely agree, children have uncanny similarities to their parents - even when they don't know their parents acted that way, for example, sitting in a desk.
We have something in my family that we call the "flashlight gene". When you see some very very specific behavior one generation to the next, it's amazing! My best friend's first son started hoarding flashlights when he was about two, all he wanted for his birthday was different kinds of flashlights, etc. How funny to learn his dad was EXACTLY the same way - obsessed with flashlights. In my family, my middle son would sneak the metal bobbin out of my sewing machine and carry it around in his pocket. Soon he had amassed several bobbins, that he carried around in his pockets. My mother in law and had a great laugh - my husband had done the same thing and she couldn't figure out where her bobbins were going either!!
Brains are amazing things.
I think your mother is very accurate in her assessment. There are many children who are raised in HORRIBLE conditions -- abused, neglected -- and they manage to lead wonderful lives as adults. There are many children who are raised in stable, loving environements who have tremendous problems/ issues. I think natural disposition is what allows people to turn their environment into their reality ( aka disposition/ genetics determine perception, which is the basis for psychology and personality.)
I think that genetics play a far more important role in personality than most people think.