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Toddler Aggression

Toddlers: Why the Bad Seed Theory Is Kind of True

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Every parent of a toddler hopes his or her kid will "play nice," and it's always a shocker when your angel suddenly turns into a biting, hitting, and kicking little beast. While good parenting may indeed help thwart unwanted behavior, kids are actually preprogrammed for aggression, according to new research.

Related: Seven Common Household Items That Are Hidden Dangers For Toddlers

A study that gathered data from more than 1,200 children ages 1 to 4 found that, to a large extent, a toddler's tendency toward physical aggression stems from a genetic predisposition and is not caused by environmental factors such as watching violent cartoons or witnessing domestic strife. If you happen to have one of the more aggressive kids on the block, the odds are it's going to pass, and you needn't become overly alarmed and blame yourself. "Parents often feel guilty," lead author Eric Lacourse, a professor at the University of Montreal, tells Yahoo Shine. "They should look at physical aggression as a normal phase of development." While tantrums and other forms of acting out may be related, the data specifically focused on violent behavior.

The study, which compared over 660 sets of nonidentical and identical twins, found that the pairs who shared 100 percent of their DNA were far more likely to exhibit the same patterns of aggression than fraternal twins. In a statement, the researchers said that their results challenge previous studies of single children "in which many family or parent level factors were found to predict developmental trajectories of physical aggression during preschool." It added, "Our results suggest that the effect of those factors may not be as direct as was previously thought." Simply put, in the case of toddler aggression, nature appears to trump nurture.


The study notes that in kids between the ages of 1 and 4, aggression peaks, and most children mature out of violent behavior. "There is no such thing as 'terrible 2s,'" adds Lacourse, who says that the onset, duration, and intensity of the unpleasant behavior vary significantly from kid to kid.

The researchers' analysis doesn't completely let parents off the hook, though. Lacourse says that the way parents deal with their toddlers' aggression can either help them grow out of it or perpetuate the cycle beyond early childhood and encourage chronic violent behavior. Young children can get stuck in a dynamic of blame and hostility with those around them, which disables them from maturing beyond the unwanted behavior. "Because early childhood propensities may evoke negative responses from parents and peers, and consequently create contexts where the use of physical aggression is maintained and reinforced, early physical aggression needs to be dealt with care," the study warns.

Parents should be neither too coercive nor too lenient, according to Lacourse. It's important to swiftly identify and discipline aggressive behavior in young children with age-appropriate punishments such as time-outs, he says. Harsh actions like screaming, spanking, or withholding love and affection may exacerbate the problem. Lacourse adds that if the behavior persists or parents feel overwhelmed, they should talk to their pediatrician about coping strategies or the possibility of other disruptive factors such as attention deficit hyperactivity disorder (ADHD). But in general, parents can rest assured that, for the majority of kids, being a terrible toddler is just a phase.

— Sarah B. Weir

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