And we're back with the provocative research that we've all been talking about and discussing, what happens when parents have a favorite child. It's part of a brand-new study in "the journal of child... See More
And we're back with the provocative research that we've all been talking about and discussing, what happens when parents have a favorite child. It's part of a brand-new study in "the journal of child development." And shows that favoritism can have a negative impact on the entire family. Honey, we have an hour before the competition. Reporter: Even for this "modern family," it's considered the cardinal sin of parenting. I like it too much when you win. Reporter: Favoring one of your children over the other? Go get it. Reporter: This father of two endured serious backlash last september, when he posted a blog, saying he liked one son more than the other. He's just the one I relate to easier. And if that means he's my favorite and those are -- that's the language, I don't think that's too evil. Reporter: But now, a university of toronto study reveals that a parent's preference for one child, especially when it's obvious, can negatively affect the entire family, even the child getting all the attention. It's really mainly when children perceive the parenting differences to be unfair that they're most reactive to that themselves. Reporter: Days before baltimore ravens head coach john harbaugh faced off against his brother, jim, at the super bowl, he jokingly called into a press conference given my their parents. Is it true that you like jim better than john? Is that john? Reporter: Perhaps john harbaugh had the right idea. The research says if one sibling acts out, he will ultimately win the attention. A dynamic that could create lasting problems. No kidding. With more on this, let's bring in abc news senior m correspondent, dr. Jennifer ashton. We've been debating this here. Is it true that parents, most parents, have a favorite child? I think most parents might have an inclination towards one child over another. But we're talking in this study about dramatically positive and negative behavior. We're not talking about parenting children differently. We're talking about being very negative to one and maybe positive to the others. My first reaction, when I read the study was, oh, no. Do I have to add this to the list of the many things I may be doing wrong. But we're talking here about dramatic examples. How often does that happen? Apparently it happens quite a bit. And the consequences here are not just for the child who is treated negatively, but for all the other siblings in the family, and not just at that time. Long-lasting with effects into their adulthood, in terms of how they interact and have social relationships, the anxiety levels. Long-term consequences are significant. It's a no-brainer that the child who isn't the favorite would feel badly. child who is favored also feels guilt. It could be guilt. They could be looking to the mother, usually. Everything falls on us, to be consistent. And when they see that consistency is disrupted, it can be unsettling. It's saying it's not just a give and take between two people in the family. It's the family as a unit. It's more than the sum of its parts. And it affects everyone. And quickly. Mothers under stress tend to show favoritism more often? Mothers who have stress in their back lives tended to be more negative. It all comes down to us. We have a hard job. Another thing. All right.
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