I think it's a bit of both nurture/nature. In hindsight it was obvious that I would be a programmer even though I didn't have much access to a computer until college. Growing up I gravitated towards math/science, loved any sort of problem solving, and enjoyed things that many would consider tedious (building model WW2 naval ships with my grandfather for example). I did have a Nintendo that was in a constant state of being taken apart, but it did work most of the time :) When I finally had school computer time starting around middle school, they literally had to drag me off of them. Trying commands, tinkering, etc... was just...fun.

None of my friends (or parents for that matter) understood because they were mostly jocks with a few artists types mixed in. But, my friends never cared as long as they could get me out of the house to play whatever sport was in season.

To circle back around, I had a natural inclination with people like my grandfather encouraging it without really knowing.