For your entire lifetime, your parents have kept up a very, very good lie.
Whether you were the straight A sibling or the one acting out in class, your parents have led you to believe that they love all their children equally.
But science tells a different story. In research that will vindicate self-pitying siblings everywhere, sociologist Katherine Conger's recently resurfaced longitudinal study found what many have suspected all along: Parents totally have a favorite child.
Koger and her research team followed 384 families in which a pair of siblings was born within four years of each other. The research, published in the Journal of Family Psychology in 2005, revealed that 74 percent of mothers and 70 percent of fathers reported preferential treatment toward one child, according to Quartz.
The parents didn't let on which child they preferred, but Koger and her team had a theory about who felt the discrepancy most: “Our working hypothesis was that older, earlier born children would be more affected by perceptions of differential treatment due to their status as older child -- more power due to age and size, more time with parents -- in the family,” Koger told Quartz.
But the hypothesis was completely wrong: Firstborns actually reported feeling they were the preferred child more often, while younger siblings said "they could sense the firstborn bias and that it affected their self-esteem -- much more so than older kids," Science of Us wrote.
After learning the results, researchers figured that little siblings detected this firstborn bias because an older brother or sister led all of the "firsts": They were the first to win a sports game, first to place in a spelling bee, etc.
The research also found that no matter a child's birth order, every single one was suspicious of their parents liking another better. “Everyone feels their brother or sister is getting a better deal,” Conger said.
So what do we make of all of this? For one, siblings have it tough. Always competing for their parents' love, never knowing who's ahead. But the good news for brothers and sisters is that the relationship serves tons of benefits: Having a sibling may make you more intelligent, more likely to have a stable marriage as an adult and can serve as a built-in support system.
Maybe it's time, kids, for you to treat your parents with their very same medicine: Assure them that you love them both the same, too. (Wink, wink.)