Birth Order and J vs P

[Seymour]

In Big Five terms one study finds:

Middleborns seemed to represent the “rebellious” (laterborn) sibling in Sulloway's (1996) theory: in comparison to their siblings, they were less conscientious, less religious, and lower in school performance, as well as more impulsive and open to fantasy, whereas lastborns were the most agreeable and warm. In most cases, effects were similar in self- and mother-evaluation. Finally, mother ratings validated self-reported personality correlates of religion (Conscientiousness, Agreeableness, low impulsiveness and low excitement seeking) and spirituality (Openness).

(Note... Big Five to MBTI approximations: Agreeable ~ F, Conscientious ~ J, Open ~ N)

And another study finds:

Across four diverse data sets, first-borns were nominated as most achieving and most conscientious. Later-borns were nominated as most rebellious, liberal, and agreeable. The same results obtained whether or not birth order was made salient (to activate stereotypes) during the personality ratings. Overall, the results support predictions from Sulloway's niche model of personality development, as well as Zajonc's confluence model of intellectual achievement.

A third study finds:

On average, firstborns—who tend to act as surrogate parents—are more conscientious than laterborns, whereas laterborns are more agreeable, extraverted, and nonconforming.

In most studies, a significant gap between the age of sibling "resets" the birth order, so that the first child after a long gap is effectively the oldest sibling.

Also note that in most of these studies, birth order effect are statistically significant, but affect the relevant trait(s)/preference(s) by less than 2%. There are some indications that birth order effects are only significant when interacting with one's family of origin. Generally, there hasn't been strong confirmation that birth order strongly affects personality.

 

[Thalassa]

This interests me because I never really felt or behaved like the oldest child even though I was...often I felt younger inside, or like some "other" out of the order entirely (enneagram would explain the latter). Granted, I was insanely strict with myself, but not otherwise or outwardly a person of any authority. Honestly, it probably just comes down to my being unhealthy as a young one and not giving a fuck about anyone or anything but my own problems. Ugh, even if I live as a saint for the rest of my life, I'll still feel sick about my past self when I'm 72...

Ironically, moving away from the family has had the biggest positive influence on me, allowing parts of me that were always there but wilted to come alive, and many fit the traditional elder profile quite well. It turns out I'm a reborn J!

It's just interesting how often birth order can encourage traits (I think it's a cultural thing), but sometimes another influence cuts in and the personalities of the kids fit a different profile than what birth order might have us assume.

I may actually have middle traits because of grandparents influence and being surrounded by extended family (acting out being funny or getting negative attention just to secure the attention on me, I actually was once diagnosed as Histrionic by a therapist in 2007) ...but it doesn't explain my YOUNGEST ESFJ sister taking on traditional elder traits...but personality type does. She's a goddamn textbook SJ.

 

[Kullervo]

This is an interesting thread.

Well, it is just me and my younger brother. I am an INTJ and he is an ESFP, the opposite. We have no Enneatypes in common either.

 

[Southern Kross]

but it doesn't explain my YOUNGEST ESFJ sister taking on traditional elder traits...but personality type does. She's a goddamn textbook SJ.

Yeah, my younger sister is a ESTJ and she takes on quite a few of the eldest traits. She's so Extroverted, assertive and high on Conscientiousness that people think she's older than me. OTOH she was much more rebellious and less bookish than me while growing up, which is more like the youngest child, I guess.

I just think it's down to how much restriction the parents put on the kids. If they force them into birth roles too much, then that suppresses contrary MBTI traits (and heightens equivalent traits) and they end up behaving more in line with their ascribed role. If they're not as restricted by their birth roles, then they simply act more in accordance with their MBTI traits.

 

[Galena]

I may actually have middle traits because of grandparents influence and being surrounded by extended family (acting out being funny or getting negative attention just to secure the attention on me, I actually was once diagnosed as Histrionic by a therapist in 2007) ...but it doesn't explain my YOUNGEST ESFJ sister taking on traditional elder traits...but personality type does. She's a goddamn textbook SJ.

That is one way to influence it, yes. My middle sister is similarly the SFJ, and I mainly acted out my enneagram as a kid. True to what [MENTION=5871]Southern Kross[/MENTION] says, my MBTI became more discernable outside of the family structure. I may not have adhered to the roles, but they seem to have exerted a presence.

 

[Showbread]

Me (21): ESFJ
Brother (19): ENFP
Brother (17): INTJ

My parents are also both the oldest of three siblings, and both are J types.

 

[ai116]

Only child - enfp

My mom(youngest of 6) esfj
Dad (oldest of 2) ENTP

 

[Hitoshi-San]

Me - ESTP
Brother - INFP (3 years younger)

My dad is an ENxP and is the second youngest with five living siblings. They're a mix of ENFP, ESFP, and ENFJ with one IxTx.

My mom is an ISFJ and her little sister is an ENFx and her older sister is an ESxP (probably).

 

[olivetti]

Me - Oj, INFJ, 9w1, sp/so
Mother - ESTP, 8w7, sx
Father - ENFP (probably), 7w6

 

[kelric]

Not going to vote, none of the choices really apply. I'm a twin, and my sister and I are the only two kids in the family.

Sister: xSFJ
Me: INTP
Mom: ISFJ
Dad: ESTJ

I'm thinking that there's not going to be any great correlation... personality types are such a fuzzy classification anyway, and people's circumstances are just too different, even if there *is* some sort of predictability factor from birth order (or anything else, really), you're probably never going to see it in the sea of other factors. That, and I suspect that personalities are just innate.

 

[Flâneuse]

older brother - INTJ (moderate-to-strong J)
me - ISFP (strong P)