Now, my theory that I was proposing last week about preferential parental investment in sexy sons or little boys who showed phallic  behaviour, is a consequence of the Trivers Willard principle, because basically what it says is that little boys who advertised, as it were, in their childhood, evidence of their own adult reproductive success by precocious sexuality towards the women of the family and aggression towards the males, might be rewarded by preferential parental investment, a Trivers Willard effect in other words, and if, when they grew up, those oedipal sexy sons were in fact more reproductively successful, then the result would be a kind of self-perpetuating cycle of parental investment in oedipal sons who then grew up to be more reproductively successful than non-oedipal sons and, and so on .