So your 5-year-old boy wants to dress like a girl....

How far should you go in supporting him? What if you're the teacher and the parents send him to kindergarten wearing a dress?

Doctors, some of them from the top pediatric hospitals, have begun to advise families to let these children be “who they are” to foster a sense of security and self-esteem. They are motivated, in part, by the high incidence of depression, suicidal feelings and self-mutilation that has been common in past generations of transgender children. Legal trends suggest that schools are now required to respect parents’ decisions....

Cassandra Reese, a first-grade teacher outside Boston, recalled that fellow teachers were unnerved when a young boy showed up in a skirt. “They said, ‘This is not normal,’ and, ‘It’s the parents’ fault,’ ” Ms. Reese said. “They didn’t see children as sophisticated enough to verbalize their feelings.”

And then there are the parents who think they ought to give hormone treatments to young tomboy girls on the theory that they need to be spared the shocking evidence of femininity that is menstruation.