A boy is a boy or a girl is a girl is not just determined by the sex alone but by the mind. This is a psychological thing, when a boy is being treated as a girl, being taught girl stuffs with time he would soon start acting like a girl. To determine a boy as a male or a girl as female starts with what is feed into the mind and head of the child. That's why we have transgenders and same sex relationship. In rare cases we have a trait issue, in the sense that all boys have a feminine side and all girls have a masculine side but when the feminine side of the boy becomes dominant or the masculine of the girls becomes dominant that is an issue. You will hear words like Tomboy and Sissy. They feel they are trapped in the wrong body