What does that even mean? More chauvinistic male crap left over from hundreds of thousands of years ago? Let your children be who they are. Why is being compaired to a girl a bad thing? My eldest son's (age 8) favorite color is pink. He wears pink Polo shirts all the time. So what? If you care about your children it should not matter. Don't be like every other parent and teach your son he has to "be a man" to fit in (emtionless, aggressive, dirty, not able to express feelings etc). That is how men become murders, rapists and child molesters.
It's sad we have to teach children, both boys and girls, that they have to fit some kind of standard of what they are "supposed to be". It's no wonder psycholeptic medicine is a multi-billion dollar industry.