# how common is knowing a great-great grandparent? **URL:** \ **Category:** Factual Questions\ **Created:** [August 10, 2010, 3:34am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786 "2010-08-10T03:34:26Z")\ **Posts on this page:** 18\ **Page:** 3
**Author:** ![awesome](https://avatars.discourse-cdn.com/v4/letter/a/8baadc/32.png) [@awesome](https://boards.straightdope.com/u/awesome)\ **Post date:** [April 23, 2018, 10:00pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/41 "2018-04-23T22:00:07Z")
> [@Zeldar](#): > > Well, one way to go at the issue is to see what’s the youngest such a person could be. I suppose 13 would be a low child-bearing age. > > Let’s say you’re 3 and your mother is 16 (she had you at 13). > Her mother had her at 13 so your grandmother is 29. > Her mother had her at 13 so your great-grandmother is 42. > Her mother had her at 13 so your great-great-grandmother is 55. > > That could surely happen with no strain but those gals got busy having babies. If any of them delayed by a few years that old gal’s going to get older. Before too many delays she will be old enough that as you get old enough to say you knew her well, she’ll be gone. > > Is the math good? > > I’m 68 and have a granddaughter old enough to have a kid. If she goes ahead and has one in a year or so and that kid (girl let’s say) has a kid when she’s 13, I’d be in my early 80’s. So my granddaughter’s granddaughter could know me before I’m out of here, but she’d need to get old enough to know who I was pretty quick. The odds of there being 4 straight 13 year old mothers are infinitesimally small. According to this data sheet, 7,107 children were born to 13 or 14 year old mothers in 2002. [https://www.cdc.gov/nchs/data/nvsr/nvsr53/nvsr53\_07.pdf](https://www.cdc.gov/nchs/data/nvsr/nvsr53/nvsr53_07.pdf) . That is out of 4.2 million births in the US. Meaning that about 0.16% of babies were born to 13 or 14 year olds. (Only 208 births were to mothers under 13.) I know this is outdated but it’s the most recent info I can find. Furthermore I assume a vast majority of the young teenage mothers were 14 rather than 13. If you assume 80% of these mothers were 14 then that means about 0.032% of mothers in the US were 13. If you include the 208 mothers under 13 it barely affects the percentages. Imagine the odds of this happening for 4 straight generations. It would be .00032^4. Which according to my google calculator is 1.048576e-14. I would be shocked if there is a single 52 year old great great grandmother anywhere in the US. I would even assume that there is not a single 52 year old great great grandmother anywhere in the world. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 23, 2018, 11:42pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/42 "2018-04-23T23:42:02Z")
> [@](#): > > Imagine the odds of this happening for 4 straight generations. It would be .00032^4. That’s an incorrect calculation. That would only be true if there were no correlation, but a young mother is likely to live in a subculture where young motherhood is common, and so her daughters would also be likely to have children young. Plus there would be genetic correlations of when they’d reach reproductive maturity, and possibly also even dietary correlations. The correct probability couldn’t be calculated, but must be determined from observation. ---
**Author:** ![awesome](https://avatars.discourse-cdn.com/v4/letter/a/8baadc/32.png) [@awesome](https://boards.straightdope.com/u/awesome)\ **Post date:** [April 24, 2018, 3:42am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/43 "2018-04-24T03:42:19Z")
> [@Captain\_Midnight](#): > > On the other end of the spectrum, John Tyler, the 9th President of the United States has two living grandsons. John Tyler was born in 1790 and died in 1862. He had a son when he was 63, and that son had two sons when he was elderly with an obviously younger woman. > > [President John Tyler has two living grandsons](http://www.amnation.com/vfr/archives/012703.html) > > I don’t know this, but it is very possible that my grandmother was held as a baby by people who fought in the Civil War and even knew of life before that time. There is a picture in my father’s house of my grandmother’s parents, which was taken, I would say around 1900-1910 by the style of clothing and the professionalism of the photograph. So their parents would have been definitely people born and likely died in the 19th Century. Amazing. And I looked it up-apparently Tyler’s grandsons are still alive in 2018. ---
**Author:** ![awesome](https://avatars.discourse-cdn.com/v4/letter/a/8baadc/32.png) [@awesome](https://boards.straightdope.com/u/awesome)\ **Post date:** [April 24, 2018, 3:54am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/44 "2018-04-24T03:54:50Z")
> [@Chronos](#): > > That’s an incorrect calculation. That would only be true if there were no correlation, but a young mother is likely to live in a subculture where young motherhood is common, and so her daughters would also be likely to have children young. Plus there would be genetic correlations of when they’d reach reproductive maturity, and possibly also even dietary correlations. The correct probability couldn’t be calculated, but must be determined from observation. Even if the culture theoretically doubled their odds of having a child at 13, the odds would still be infinitesimally small. And there’s something else that would make a 52 year old great-great grandmother almost impossible that I didn’t think of in my last post. Even if you somehow had 4 generations of 13 year old mothers, the great-great grandmother probably wouldn’t be 52 at the time of the birth of the youngest. In order for this to happen the age of the 4 mothers at birth would have to average less than 13.25. If they’re all 13.25 at the time of the birth, then the great great grandmother would be 53 at the time of the last birth. In theory the great great grandma could be as old as 55 years and 361 days, if all 4 of the mothers had children the day before their 14th birthday. Plus this event requires that everybody in this sequence except for the last mother has a girl as her first child. Unless they have a son who becomes a father at age 13. Which I assume is even more rare than a girl having a child at 13. ---
**Author:** ![cmkeller](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmkeller/32/118_2.png) [@cmkeller](https://boards.straightdope.com/u/cmkeller)\ **Post date:** [April 24, 2018, 5:06am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/45 "2018-04-24T05:06:16Z")
I’m surprised I didn’t respond to this thread in its first life. My oldest son was born with a living great-great grandmother, and, like two of the earlier posters, our 5-generation photo of him, her, and the three generations in between (all women) is one of our most prized family photos. My recently-deceased (only two months ago) grandfather got to meet his great-great grandson last summer. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 24, 2018, 1:46pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/46 "2018-04-24T13:46:35Z")
> [@](#): > > Even if the culture theoretically doubled their odds of having a child at 13, the odds would still be infinitesimally small. If the odds are only doubled. The increase could be much, much higher. If, for instance, the subculture in question is a child-abusing cult. Which are thankfully rare, but the existence of even one such cult would drive the occurrence much higher than your calculation. ---
**Author:** ![blood63](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@blood63](https://boards.straightdope.com/u/blood63)\ **Post date:** [April 24, 2018, 5:22pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/47 "2018-04-24T17:22:38Z")
> [@Zeldar](#): > > Well, one way to go at the issue is to see what’s the youngest such a person could be. I suppose 13 would be a low child-bearing age. > > Let’s say you’re 3 and your mother is 16 (she had you at 13). > Her mother had her at 13 so your grandmother is 29. > Her mother had her at 13 so your great-grandmother is 42. > Her mother had her at 13 so your great-great-grandmother is 55. > > That could surely happen with no strain but those gals got busy having babies. If any of them delayed by a few years that old gal’s going to get older. Before too many delays she will be old enough that as you get old enough to say you knew her well, she’ll be gone. > > Is the math good? > > I’m 68 and have a granddaughter old enough to have a kid. If she goes ahead and has one in a year or so and that kid (girl let’s say) has a kid when she’s 13, I’d be in my early 80’s. So my granddaughter’s granddaughter could know me before I’m out of here, but she’d need to get old enough to know who I was pretty quick. Yes, but women in the past did not reach sexual maturity until the age of 16 or so. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [April 24, 2018, 5:29pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/48 "2018-04-24T17:29:53Z")
> [@blood63](#): > > Yes, but women in the past did not reach sexual maturity until the age of 16 or so. [It varied by era and nutrition](https://www.bustle.com/articles/114490-the-average-age-women-got-their-first-period-throughout-history). Victorian era average was 14 years old (13.5 for upper class, 14.5 for working class.) Middle Ages it looks to be about 14, and Renaissance about 16, also varying with nutrition. ---
**Author:** ![awesome](https://avatars.discourse-cdn.com/v4/letter/a/8baadc/32.png) [@awesome](https://boards.straightdope.com/u/awesome)\ **Post date:** [April 24, 2018, 9:31pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/49 "2018-04-24T21:31:03Z")
> [@Chronos](#): > > If the odds are only doubled. The increase could be much, much higher. If, for instance, the subculture in question is a child-abusing cult. Which are thankfully rare, but the existence of even one such cult would drive the occurrence much higher than your calculation. Apparently there was a 23 year old grandmother in the U.K. [Rifca Stanescu: Gypsy wife is world's youngest grandmother at 23 | Daily Mail Online](http://www.dailymail.co.uk/news/article-1363699/Rifca-Stanescu-Gypsy-wife-worlds-youngest-grandmother-23.html) Her child and grandchild would still have to have children at a combined age of 29 or younger in order for her to become a 52 year great great grandma though. With that being said this women is a gypsy. A group of people who often have children young. There aren’t any Gypsies in the US so an event like this would be less likely in America. I’m a little skeptical about the idea of a child abusing cult existing for 52 years. I think such a cult would either be broken up by the government or dissolve on its own after a lot less than 52 years. Especially if it’s getting children pregnant. ---
**Author:** ![awesome](https://avatars.discourse-cdn.com/v4/letter/a/8baadc/32.png) [@awesome](https://boards.straightdope.com/u/awesome)\ **Post date:** [April 24, 2018, 9:35pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/50 "2018-04-24T21:35:45Z")
The only info I’ve been able to find about America’s youngest grandma is this 1954 magazine. Which said the youngest grandma in America at the time was 29. [Jet - Google Books](https://books.google.com/books?id=wr8DAAAAMBAJ&pg=PA24&lpg=PA24&dq=america+youngest+grandmother&source=bl&ots=inpvDA6Xov&sig=gavii6eyx1aaG3NcMw67-M3-b4A&hl=en&sa=X&ved=2ahUKEwiQs5eT7tPaAhULvVMKHZQ3Bek4ChDoATACegQIBxAB#v=onepage&q=america%20youngest%20grandmother&f=false) Even if the process repeated itself in the next 2 generations this would have only resulted in a 58 year old g-g-grandma. ---
**Author:** ![sbunny8](https://avatars.discourse-cdn.com/v4/letter/s/c77e96/32.png) [@sbunny8](https://boards.straightdope.com/u/sbunny8)\ **Post date:** [April 25, 2018, 12:12am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/51 "2018-04-25T00:12:21Z")
> [@Zeldar](#): > > I suppose 13 would be a low child-bearing age. > Let’s say you’re 3 and your mother is 16 (she had you at 13). > Her mother had her at 13 so your grandmother is 29. > Her mother had her at 13 so your great-grandmother is 42. > Her mother had her at 13 so your great-great-grandmother is 55. > Is the math good? No, there are problems with your math. #1 You assumed that they moms gave birth at exactly 13 years of age, not 13 1/2 or 13 3/4 etc. Of all the women who said “I had a baby when I was 13”, you’d expect the majority to be much closer their 14th birthday than their 13th. #2 Even if they did all gave birth at 13.00, that means they all got pregnant at 12 1/4. Given that, on average, most women have sex several dozen times before getting pregnant (that’s with no birth control), they probably started having sex before their 12th birthday. Yikes. So, instead, let’s assume that these [Little Darlings](https://en.wikipedia.org/wiki/Little_Darlings) had sex starting on their 13th birthdays and got pregnant around 13 1/2, giving birth at 14 1/4. That means the great-great-grandmother is (14 1/4) x 4 = 57 years older than the great-great-grandchild, **at minimum**. If the g-g-g-child is 3, the g-g-g-mother is at least 60. And, as others have pointed out, that would be an extraordinary run of luck. I think it’s much more realistic to figure 18x4=72 year age gap. If g-g-g-maw died at 80, you could still remember her from when you were 8 or younger. ---
**Author:** ![TonySinclair](https://avatars.discourse-cdn.com/v4/letter/t/49beb7/32.png) [@TonySinclair](https://boards.straightdope.com/u/TonySinclair)\ **Post date:** [April 25, 2018, 12:24am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/52 "2018-04-25T00:24:39Z")
Just to show that there are always outliers, my dad just turned 100, but only two of my grandparents and nobody farther back were alive when I was born, and both of them died before I was 20. AFAIK all deaths were from natural causes. ---
**Author:** ![Shamozzle](https://avatars.discourse-cdn.com/v4/letter/s/9f8e36/32.png) [@Shamozzle](https://boards.straightdope.com/u/Shamozzle)\ **Post date:** [April 28, 2018, 4:38am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/53 "2018-04-28T04:38:48Z")
I work with a woman who is currently both a grandmother and a granddaughter. She’s 50. That all I have to say, whatever that’s worth. ---
**Author:** ![David\_Partridge](https://avatars.discourse-cdn.com/v4/letter/d/dc4da7/32.png) [@David\_Partridge](https://boards.straightdope.com/u/David_Partridge)\ **Post date:** [April 14, 2020, 11:36pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/54 "2020-04-14T23:36:10Z")
Hi. I am 66 years old with 2 Great Grandchildren, the eldest is a 10 year old boy. I am hoping to see him have children. I think I could be in with a chance of becoming a Great Great Grandad. ---
**Author:** ![gkster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gkster/32/14107_2.png) [@gkster](https://boards.straightdope.com/u/gkster)\ **Post date:** [April 15, 2020, 3:29am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/55 "2020-04-15T03:29:20Z")
Zombie great-great-grandparents? I clearly remember my great-great-grandmother. She died at age 94, when I was 7, and there are at least 4 of us in my generation (my siblings and cousins) who met her and were old enough to remember her. However I’m one of the eldest in my generation; I have first cousins who are 25 and 30 years younger than me. ---
**Author:** ![Aspidistra](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aspidistra/32/3894_2.png) [@Aspidistra](https://boards.straightdope.com/u/Aspidistra)\ **Post date:** [April 15, 2020, 4:59am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/56 "2020-04-15T04:59:33Z")
> [@David\_Partridge](#): > > Hi. I am 66 years old with 2 Great Grandchildren, the eldest is a 10 year old boy. I am hoping to see him have children. I think I could be in with a chance of becoming a Great Great Grandad. Cool! That’s probably more rare, what with men generally having kids at a later age than women. Is the link between you and your great grandson an all-male link, or mixed M/F? You could get a good multi-generation photo out of that 🙂 ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [April 15, 2020, 10:03am UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/57 "2020-04-15T10:03:39Z")
No chance for me becoming a ‘great’. since I am in my 70s and our only granddaughter is just 3. She is slightly unusual though in that she is the only grandchild of all four (still living) grandparents. By the time she reaches 18, she could be quite a wealthy young lady. ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [April 15, 2020, 12:22pm UTC](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786/58 "2020-04-15T12:22:40Z")
I did some quick checking on my family tree for a couple generations. The only “hit” I found was the one I already knew was there. My mother’s gg-grandmother was alive for 14 years after my mother’s birth. They lived in the same area for a while before my mother’s family moved away. My mother would have known her. Problem: my mother’s memory of such stuff was never great. She didn’t really remember her except a vague memory of attending her funeral. So out of 6 people I checked with 16 gg-grandparents each giving 96 total opportunities, there was only 1 match. I suspect that that is higher than average. (So up until last year there was a family member who knew someone who was born in the 1850s whose g-grandfather fought in the Revolution … as a Hessian. Got captured and decided to stay.) [Previous page](https://boards.straightdope.com/t/how-common-is-knowing-a-great-great-grandparent/549786.md?page=2)