This is just biological reality, the idea didn’t have to come from anywhere other than observing humanity. You are your father’s son—all personality traits demonstrate high genetic inheritability, including sense of humor, taste, etc. The rest is largely derived from childhood environment, which is still a product of your parents. The thought experiment of “what if you were born in Sudan” is the same as asking “would you still love me if I was a worm?”. The “you” is not Sudanese any more than your gf is a worm. You could have been born a worm, but you weren’t, and even if you were, the “you” does not transfer. The worm cannot and will not ever be you, anymore than you could ever be Sudanese; and your girlfriend would not love you if you were, even if we allow that a Sudanese could be loved, because the Sudanese you is not you, not anymore than she is a worm.