Heights of same sex siblings (bit of fun)

[ChangeNameLikeIChangeSocks]

Inspired by this thread about the sex of your third baby https://www.mumsnet.com/talk/am_i_being_unreasonable/4959091-3-kids-gender-stats-probability

So thank you blackcoffeeandchocolate

My question is, I read that with siblings of the same sex the elder is more likely to be taller, as they have used up a lot of the nutrition/newness available in utero. This struck me as a load of nonsense.

But more than that, I can think of loads of examples of same sex siblings where the elder child is the shortest.

Both of my parents and their siblings
The chuckle brothers
Me and my sibling
DH and his siblings
DC1 and DC2 (based on same age-for-age comparison)

And by the way, hilarious that all of these from my family are all same sex groupings with no additional third sibling of the opposite sex. I read something else once that said "nobody knows why some families tend to have only boys, and some only girls"

I'm sure there are loads of siblings that do follow an opposite trend, which is why I wanted to ask, if you have a sibling of the same sex, or who is taller?

One or two?

The poll

• yabu - one

Yanbu - two

My very technical and professionally hypothesised opinion is that since your womb has already been stretched (in the nicest possible way) with the first, you can stretch a little bit further for the second? 😂 in my children's case the second stayed in two weeks longer so maybe grew a bit more then??

I have 2 boys, now adults.
DS1 was longest as a baby but DS2 was heavier. DS1 seemed to stop growing and was below average up until 15/16 when he finally shot up. DS2 was always slightly above average.

At 22 and 18 they are both now exactly 6’1. Same as their dad and their paternal granddad.

I am 5ft6 my younger sister is 5ft10.

I've got 4 brothers, the oldest is 6 3, the 2bd is 5 10, the 3rd 6 1 and the youngest 5 6.
There's also 3 sisters, I'm the oldest at 5 5, middle is 5 9, youngest is 5 6.
I have no idea what went on as our dad is 6 3 and mum 5 10 🤷‍♀️

DH is the youngest of 7 brothers
Order of heights (tallest to shortest)
2
7(DH 5’11.5)
6
5
4
1
3 (around 5’5)

So I am not convinced the theory holds up for big families especially where there is a big height difference between the parents. MIL was around 5’3 and FIL close to 6’.

2 biys , ds1 is 6ft1 , ds2 is 5ft 9
ds1 was longer when born as well but was very short for his age until around 16. Ds2 always shoft for his age from around 3 upwards

I’m the elder of 2 sisters and both 5’7 as is my mum. Dad 5’9

I only have one child, DS who is 18 and 5’11 same height as his dad

I have 3 sisters

1st - 5'4
2nd ( me ) - 5'1
3rd - 5'6
4th - 5'1

H is shorter than his younger brother.
our family doctor has predicted DS2
will be taller than DS1
My stepsister 1 is shorter than stepsister 2

My maternal uncles, the second born was taller than first born and taller
than all the other sons born after

I'm the youngest in my family and my older sister's taller than me... but to be fair, I'm only 5'2" so most people in general are taller than me, siblings or not.

For my cousins, both male, the elder one was taller.
My grandmother and her sister, the younger one was taller.

My little sister took over me in height when we were young. My younger brother is taller than my older brother.

My younger brother if the youngest out of the 4 of us and he's 6ft 4

OMG this is so true in my case shorter with big tits

DD15 - 5ft 1
DD13- 5ft 5

DD15 was a very big baby, 10lbs 14oz and 24 inches. She's the smallest in height in her class/sports team etc. DH and his family are not tall so she must take after them.

Eldest girl - smallest, and smallest feet too
Middle boy - unsurprisingly, tallest
Youngest girl - middle height (5ft 4)

My older sister is taller than me but my husband is the youngest and tallest so there's an example for both ways.

In my family eldest brother is 6ft 1. Younger brother is 5ft 8.

My brothers kids, younger DD 3 inches taller than eldest

Couple of families of all boys. One goes DS2, DS1, DS3. Other family is DS3, DS2, DS1.

So absolutely no pattern that I’ve observed.

OP your theory holds true for my family. We are 4 sisters, all in our 50s now.
Oldest is. 5’3”
middle (me) 5’4”
younger sisters fraternal twins, both 5’5” (maybe one is 5’5.5”)
What I’ve always thought Interesting is oldest sis and I were healthy babies 7lb and 8lb, but the twins were micro preemies, 2.5lb and 3lb, but still ended up tallest.

My sister and I are about the same height.
of my four sons, they rank no2, no4, No1 and no3 from shortest (5'6) to tallest (6'2)
The tallest was one day early and the others were all late, 2 by ten days, and one by a week.
I'm only 5'3, and DH is exactly 6foot.
DD is in the middle, both with birth order and height.

DD2 is 7 inches taller than DD1. 5’10” & 5’3”.
My sister is 2 inches taller than me.

I'm 5'7", DH 5'11". DD1 = 5'5" age 18, DD2 5'10" aged 14. DD2 was a longer and heavier baby and has always been tall for her age.

Not in my family. I'm the youngest and the tallest. My middle sister, in the middle.

My two sons, the younger one is taller.

Surely it's the genes more than the environment (although there is some environmental influence, obviously.). I take after my mother's body shape - taller genes, and my sisters take after my dad's.

I’m the elder sister (oldest of 3, 2 girls and a boy) and I’m taller than my sister by a couple of inches.

DH is the middle boy and third of 4 kids. He’s 6’5 and his brothers are 6’2 and 6’1

My big sis is two years older than me. She is 5'8", I'm 5'2 (and a half).

I'm seeing that for a lot of families it can be random, or the opposite, but the poll has it currently that 64% do have it that the youngest is taller. Fascinating!

Maybe the womb is more experienced??

Perhaps I should also do a thread on Sex, because all the sets of siblings I cited in my op are all single sex only.

Out of interest, here is one of the studies I read that showed that elder children were taller, though it doesn't explain much detail in clear English!
https://pubmed.ncbi.nlm.nih.gov/23347499/#:~:text=There%20was%20an%20incremental%20height,P%20%3D%200%C2%B7007).