The Sibling Who's Least Likely To Cheat, According To Research
Your birth order may say more about your loyalty than you think.
Getty Does birth order have anything to do with cheating? According to research, yes, it seems so. Ask any scorned partner, and they’ll swear up and down they’ve got a sixth sense when it comes to cheaters.
They can pick the unfaithful out of a crowd based on a person’s hairstyle alone, or some other counterintuitive indicator. While this might certainly be a special talent, there’s likely no actual science behind it.
However, a study published in 2002 built on previous research to explore how birth order might affect relationships with family and friends.
According to research, the sibling who is least likely to cheat is the middle child.
Why are the middle siblings less likely to cheat?
According to the study, there is evidence that the middle sibling might be the least likely to cheat and step outside of the perimeters of monogamy. (Insert the sighs of relief from middle children everywhere.)
"Middle-borns expressed more positive views toward friends and less positive opinions of family in general. They were less inclined to help family in need than first-borns or last-borns. Mating strategies also appeared to be influenced by birth order, most notably in the area of infidelity, with middle-borns being the least likely birth order to cheat on a partner."
In the study, "subjects were given a series of statements about attitudes toward friends and friendship and asked how true such a statement was for them. Middle-borns expressed significantly more positive views on friendship and its benefits than either first-borns or last-borns."
The study also found, "middle-borns reported cheating on a partner in a monogamous relationship significantly less than did first-borns or last-borns." So it suggests "middle-borns are interacting with mates in much the same way as they interact with friends, being careful to maintain high-quality relationships in both areas."
What about an eldest sibling's propensity to cheat?
Ground Picture via Shutterstock
Ask any person who is the eldest sibling, and they’ll most likely tell you they feel they’re put under a much brighter (some might say “harsher”) parental spotlight than their brothers and sisters.
Since they were the only child in the family to have received uninterrupted one-on-one time, the expectations are higher, and therefore, the stress of meeting those expectations is as well.
This is reinforced by the findings of another study on birth order and goal orientations, "birth order lies at the heart of people’s goal preferences as we consistently found that first-borns have developed a preference for mastery goals.
Those goals are based on self-referenced standards of competence, whereas second-borns have developed a preference for performance goals (which are based on other-referenced standards of competence)."
Other studies have indicated that the eldest are also more likely to experience more success in their careers due to their birth order and being born into the natural position of leadership among their brothers and sisters. Not that this news equates to imminent doom for those who are romantically involved with someone who happens to be the first-born.
What about the youngest sibling's propensity to cheat?
As for the youngest sibling, the study referenced previous work that showed "birth order to play a role in parental investment," The child's "expected contribution to parental fitness resides mainly in reproductive value (expected future reproduction) and this increases with age, making an older child more valuable from the parental perspective than a younger one."
The oldest sibling feels the parental pressure to reproduce, while the youngest sibling is almost off the hook from familial reproductive obligations. The study continued, "expectation of parental favoritism that makes first-born children defenders of parental values and the status quo while later-borns are relatively inclined to be rebels."
This whole time, the middle child is working on building their network of friends. Perhaps sibling rivalries play a role — the eldest and youngest, after all, are synonymous with being the apple of their parents’ eyes, while the middle child gets left with a side-eye.
Is classic sibling rivalry to blame?
Prostock-studio via Shutterstock
Historically, the eldest has to have it all, the middle child just wants someone to remember their birthday, and the youngest is on a constant search for new boundaries to cross and rules to break, because their parents are too preoccupied with singing the eldest’s praises while also keeping the scorned middle child at bay to pay attention to the youngest‘s rebellion.
I’m an only child, so though it pains me to say it, the researchers might be the more trustworthy source in this case.
If you’ve got siblings, what do you think? Are your siblings keeping secrets to maintain their position? Or is this just another study that’s going to give those who are in happy relationships another reason to sleep with one eye open?
Hannah Westmoreland Murphy is a writer for Bustle, SheKnows, Scary Mommy, Romper, and more. When not chasing her two boys and husband, you can find her obsessively reorganizing her house, moonlighting as a medical professional, and yelling at the TV.
