I recall a girl I knew briefly in summers 4th-6th grade meeting me as an adult almost 40 years old and saying "You are just like you were then." I didn't like the comment at all. I had been a committed Christian for 16 years, had been educated in a different part of the country, married, had children, read many things, and thought I was a very different person now. Plus, everything I had been taught to date suggested that environment, decision, developed character and the like were the big issues. Genetics had its place, but it was minor.
It turns out that Susie Creamer of Chelmsford, MA may have been more right than the experts. It's not just height, and IQ, and musical or athletic abilities. Sumus quod sumus.