In Japan there is mukoyoshi, when a family will legally adopt an adult who then runs the family business in addition to marrying the eldest daughter. I once met a Scandinavian guy who had moved to Shanghai as an 18yo in the 2000s and became adopted son and scion of a v powerful family. There will be interesting intersections between eugenics, adoption, surrogacy, and business in this century. The first trillionaire will likely be an adopted son conceived via eugenics and born via surrogacy.