Your baby's way of handling stress
Everyone gets a smidgeon freaked out about pregnancy, but if your anxieties are on overload, you stand a good chance of having a baby who's as nerve-addled as you are. Studies have shown that the more on edge Mom is, the more negatively baby reacts to trying situations. Experiencing lots of stress in pregnancy (the kind that comes from moving or fighting with your partner) can make it harder for baby to relax, even if you're generally laid-back. Researchers suspect that Mom's stress hormones actually affect her fetus's central nervous system.
Rather than taking a swig of guilt juice for passing along your knack for worrying, focus on the good news: Nature isn't destiny. Even a kid born with a gene that makes it hard for him to settle down can ditch the anxiety by age 1 if he has a responsive mother early on, says Cathi Propper, Ph.D., a research scientist at the University of North Carolina's Center for Developmental Science, in Chapel Hill. Bottom line: Keep calm and carry on.
Your baby's silly sense of humor
You crack up watching videos of lunatic cats on YouTube and, funny, so does your baby. So did she get her sense of humor from you? To a point. A quick-to-laugh disposition can be part of your baby's natural temperament, the bundle of personality traits that are, at least in part, genetically inherited. (Your child's mood, attention span, and activity level are also aspects of her temperament.) Where babies come by most of these characteristics isn't entirely clear. "Both genetic and environmental factors can influence temperament," says Brian D'Onofrio, Ph.D., an assistant professor in the department of psychological and brain sciences at Indiana University in Bloomington. And when you notice your kid's temperament is similar to your hubby's or your own, it's safe to assume that he either got some of your hand-me-downs or picked up aspects of your personality living under the same roof.
Still, humor is for the most part social, something your baby figures out by watching you. "When moms and dads do absurd things, like blowing raspberries or speaking in a silly voice, babies don't know what to make of it, but their parents tell them how to respond by smiling and laughing," explains Gina Mireault, Ph.D., a professor of psychology at Johnson State College, in Johnson, Vermont, who studies humor in babies. When you snicker, be it at your stinky dog or your baby's goofball faces, your munchkin is likely to start laughing too. As she gets older, she'll develop her own ideas about what's funny. Still, she'll probably always think that cracking you up is killer, meaning that she'll naturally gravitate toward whatever makes you chuckle -- even online cats.
In the end, what matters isn't deciphering your kid's intricate DNA code. Says Dr. D'Onofrio, "Better to ask yourself, 'Given my child's temperament, her own difficulties and strengths, what can I do best to parent her?'" If you let your answer guide how you mother, nature and nurture can work together -- no matter whom your child resembles.
Originally published in the December/2010 issue of American Baby magazine.