I always wondered if some political differences were rooted in sibling rivalry and identity forming (ie one child learns to defend parent's "traditional" values, so the other becomes the "rebel", and each has plenty of support in our freethinking Nation). My 2 boys Centrist (so far). I tried hard to immerse them in divergent activities so as to learn to be the "bridge" (oh Lord, was that ever the position I was forced to have). They both did sports then at times had to run to the music concerts in their uniforms. When asked on college apps for situations of leadership, the youngest said "the football guys hated band, band guys hated football, and I had to try to get along with them all"...Bingo!