As they get older, studies have shown boys are encouraged to more actively explore their environment, while girls are encouraged to engage in quieter play.
"Even if your boy prefers playing with a truck, make sure you talk to him and teach him about nurturing," Gilliam said. "Even if a girl is playing with a doll, every once in a while throw her a ball or take her on a run. Expose them to all the different possibilities, and then let them choose."
And keep in mind just how much you may be dragging your own stereotypical notions into parenting.
In the study, researchers found no association between parents' reported views on gender-appropriate toys for children, or parental roles at home, and the toys children chose. In other words, dads who did their share of housework and moms who held high-level jobs outside the home were just as likely to have girls who picked dolls and boys who picked cars and trucks.
But Gilliam remembers one family who brought their young son in to see him. There was an assortment of toys scattered on the floor, from which the boy chose a plastic figurine. "The mom said, 'Oh, he wants to play with dolls.' And the father replied, 'He's not playing with dolls. Those are action figures.'"
The International Play Association has more on why it's important for children to play.
SOURCES: Sara Amalie O'Toole Thommessen, student, City University, London; Walter Gilliam, Ph.D., associate professor, child psychiatry and psychology, and director, Edward Zigler Center in Child Development and Social Policy, Yale University, New Haven, Conn.; April 15, 2010, presentation, British Psychological Society annual conference, Stratford-upon-Avon
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