Children whose behavior doesn't conform to gender expectations — girls who swing swords and play with trucks, boys who tend to dolls and are drawn to high heels and frilly dresses — are only rarely tipping their hand about their future sexual orientation. But such behavior does predict that a kid is more likely to experience psychological, physical or sexual abuse during childhood, and will go on to suffer post-traumatic stress.

Behavior that defies gender stereotypes is remarkably common, reports an editorial published alongside two studies on gender-defying kids in the journal Pediatrics last week.

As many as 13 percent of teenage boys and 26 percent of teenage girls report that they engaged in cross-gender behavior as younger kids.

And between 2 percent to 5 percent of boys and 15 percent to 16 percent of girls reported they sometimes wished they could be the opposite gender.

Such behavior can hint at future sexual orientation or gender identity, but not with great accuracy.

A new study published in Pediatrics finds that, of children who most intensively engaged in behavior that crossed gender stereotypes (the top 10 percent), about 60 percent between the ages of 19 and 27 would identify themselves as heterosexual. (That still counts as a 'strong association" between child gender nonconforming behavior and homosexuality, but it's far short of predictive.)

And even fewer of those who defy gender expectations as kids will end up wishing to switch genders.

Children who wish to change genders, a second study found, have high rates of psychological distress (about 44 percent of one study sample had a history of mental health issues) and are at high risk of self-harm (with just over one-in-five self-mutilating and about 9 percent having attempted suicide).

"Our study," the authors wrote, "cannot determine the causal relationship between abuse and gender nonconformity — in other words, the extent to which nonconformity is a risk factor for abuse versus an indicator of abuse."

They concluded: "Further research to understand how gender nonconformity might increase risk of abuse and to develop family interventions to reduce abuse risk is needed."

For children who consistently express discomfort with their gender, earlier medical intervention — specifically, the administration of hormones to slow or forestall puberty — improves mental health, the second Pediatrics study found.