It's perhaps motherhood's dirtiest little secret: Favoring one child over another.
Favoritism is usually not intentional and can happen for a variety of reasons. Maybe one kid is the most well-behaved in the brood, especially talented, has an inexplicable bond with a parent. And often times the opposite can be true: If one child has behavioral problems, he can become the favorite because he requires extra attention.
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And while moms may objectively realize that favoritism isn't ethical or even a conscious act, a new study published on Tuesday in the February issue of the journal Child Development shows that showing more love to one kid harms more than just the "naughty one"—it damages the entire family unit, causing increased mental health problems in children such as aggression, attention, and emotional problems.
The study included 400 Canadian families with up to four kids each whose average age ranged from 2-to-5-years old. Due to the fathers' conflicting schedules, only mothers were assessed for certain "risk factors" such as education and income level, mental stability, whether they were single parents, and had suffered any past mental or physical abuse. Then, researchers assessed how much the mothers displayed favoritism which they called "differential parenting"—giving positive feedback to one child and negative feedback to another—by both observing mother-children interaction and asking the moms questions such as, "How often do you and your child talk or have fun together?" and "How often do you get angry with your child?"
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"We found that moms with more risk factors tend to favor one of their children the most," says lead study author Jenny Jenkins, Ph.D., a professor in the department of Applied Psychology and Human Development at the University of Toronto. And while a favored child may experience momentarily satisfaction, the overall home environment becomes hostile and aggressive, especially between siblings. "That the was the most surprising part," she says.
The study didn't observe why some kids are favored over others but according to Jenkins, when a family doesn't have much support or resources, it's harder for parents to treat their kids equally. "In general, parents really try their best to be fair to their children. The problem is, outside stress can affect how parents react at home. And of course there are just some kids who are more troublesome or harder to connect with than others," she says.
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"Kids are very perceptive to how they're treated in comparison to the rest of the family," says Jenkins. "Many older ones are able to understand why one sibling may need more attention at any given time but it's still important for moms to be as transparent as possible when doling out punishments or spending extra time with one child so no one feels left out."
If you find yourself getting angry with one child, try to tap into your feelings by asking yourself: Are you upset because of what your kid did or which kid did it?
And finally, as frustrating as those "It's not fair!" tantrums are, listen to them. "Often times, your child is telling you that he feels unloved," says Jenkins. "Hear those tantrums and learn from them."