Wonder what caused your child to develop a fascination with something? Look in the mirror. For while it may have been a toy, a video, or a book that triggered his interest, you're probably the one who exposed him to it and, in all likelihood, encouraged it. According to a study coauthored by Joyce M. Alexander, Ph.D., professor of educational psychology at Indiana University in Bloomington, 69 percent of preschoolers share a similar or related passion with their mom or dad. Meg Wilson, of Anderson, South Carolina, says her 4-year-old son Gardner's insatiable hunger for all things technical -- he's already devised a pulley system using his sand bucket -- stems from his father, Ken, who has an engineering degree. "My husband makes Gardner his little helper when he's installing shelving or fiddling with turntables," says Wilson.
But kids' obsessions don't always run in the family. Research published in Developmental Psychology shows that one out of three parents have no idea where their child's fascination came from. "We don't know what causes these extreme interests," says Judy S. DeLoache, Ph.D., professor of psychology at the University of Virginia, in Charlottesville. "It could just be a child's temperament that makes him gravitate toward something."
Ask yourself why you're passionate about certain things and you'd probably find it a challenge to answer. "Just as grown-ups are drawn to a specific type of music, kids find things that speak to them," says Kathleen McCartney, Ph.D., a Parents advisor and dean of the Harvard Graduate School of Education.
Those things may vary from the obvious -- pirates, cars, princesses -- to the downright quirky. Susanna Goldberg, of Charlotte, North Carolina, describes her 5-year-old son's obsession with luggage: "AJ loves to play airport, rolling our bags around the house and through the pretend X-ray machine."
Preschooler passions tend to toe traditional gender lines, says Dr. DeLoache. Boys veer toward vehicles, machines, and superheroes. Girls gravitate toward dress-up, dolls, and animals. Marketing clearly plays a role in this divide, since commercials and product packaging are often geared toward one sex or the other. Children also tend to be encouraged by their parents to play with "gender-appropriate" toys from infancy.
However, it's clearly a matter of nature as well as nurture. By 18 months girls are more interested in dolls than boys are while boys lean toward trucks and cars, according to a study published in the International Journal of Behavioral Development. Scientists speculate that these preferences are at least in part due to biological differences, says Lisa A. Serbin, Ph.D., professor of psychology at Concordia University, in Montreal, Quebec.