How many children should you have?

From a private point of view, only one:

In comparing identical twins, Kohler found that mothers with one child are about 20 percent happier than their childless counterparts; and while fathers’ happiness gains are smaller, men enjoy an almost 75 percent larger happiness boost from a firstborn son than from a firstborn daughter [TC: remember the result that fathers with sons are less likely to leave?].  The first child’s sex doesn’t matter to mothers, perhaps because women are better than men at enjoying the company of both girls and boys, Kohler speculates.

Interestingly, second and third children don’t add to parents’ happiness at all.  In fact, these additional children seem to make mothers less happy than mothers with only one child–though still happier than women with no children.

"If you want to maximize your subjective well-being, you should stop at one child," concludes Kohler, adding that people probably have additional children either for the benefit of the firstborn or because they reason that if the first child made them happy, the second one will, too.       

Here is the longer story.  See this paper.  Here is the researcher’s home page

I am hardly an expert in this area, but I find the logic appealing.  One kid is quite able to fill your time and thoughts.  I call this the "parent as empty vessel" model.  The argument for more than one kid, in this view, would rest on risk-aversion and the chance that one kid might die or not work out so well.

Note the contrast between Kohler with Bryan Caplan’s theory that you should have more kids now than you want, so you may enjoy them when you are old.  At that point in time, no single kid "fills the empty vessel" and so more of them are needed.

I believe that men enjoy children more than women do, as they are less stressed by worry.  Whether men want children more is a different question [this last sentence has been altered from a previous version.]

The pointer is from the still totally awesome


What if the maximizing number is 0.7? I mean, maybe the relevant choice variable is not the number of kids per se, but how many hours do I want spend with them. I can have one kid but send him/her to the nursery and to grandma's home for 0.3 of the day.

Is objective well-being less important than subjective well-being?

It would be interesting to see the happiness of children based on number of siblings factored into this discussion. Parents often value the long term happiness of their children over their own, so a sense that a child would be happier with a sibling may outweigh a small decrease in personal happiness.

How meaningful are these sorts of statistics? If a certain amount of people report increased happiness with less children, can this inform individuals? Perhaps personal utility is one of many competing obligations and not the foremost consideration when deciding to have children.

I'm not taking any chances that my name won't continue for multiple millenia. Seven children at least. Be fruitful and multiply.

I believe that men enjoy children more than women do, as they are less stressed by worry. Men should want more children than do women.

It seems there are other factors at play, as in my experience this is dramatically false.

I sometimes wonder whether the enjoyment of children is a giant endowment effect.


Falling birth rates in high income countries suggest people
are figuring it out.

Second kid brings sibling rivalry. Of course, single kids
are more likely to be spoiled, including having parents who
can afford to send them to a more expensive college...

cats > children

I don't think this study informs us whether we should have children or not. Women without children tend to be people who have never been married, have social problems, or are otherwise unstable: therefore, they don't have children.

So, I think, at least in the case of women without children, the causal chain should be reversed.

As a first child, these results are unsurprising.

On the grandparent angle... if you have more children than you can acceptably capitalize, you reduce your chances of them having grandchildren in a time frame you will be allowed to enjoy them.

It seems to me that the more likely a person is to make their decisions based on statistical finding such as this the less likely they are to be representative enough of the data-set of people from whom those statistics were drawn that the statistics remain significantly predictive.

From the article:

In summary, Models 4 and 8 of Table 5 reveal a striking male–female
difference regarding the effect of children on well-being after controlling
for current partnership (see also Figure 3). Females derive happiness gains
from children even after controlling for current partnership status. The happiness
of males, however, depends primarily on partnership status; once
current partnership status is controlled, men’s happiness does not vary systematically
with fertility. These findings suggest a provocative interpretation
about the motivations of men and women in forming partnerships. In
particular, the results can be interpreted to suggest that women form partnerships,
among other reasons, in order to have children who increase their
subjective well-being. Males, on the other hand, have children in order to
remain in the partnerships that strongly affect their happiness. Having children
is a strong predictor of currently being in partnerships for males (as
well as for females); but conditional on current partnership status, children
do not contribute to men’s subjective well-being.21 The male preference for
boys, revealed by our earlier analyses in Figure 2, may in this context be
the result of the higher divorce probabilities of couples who have a firstborn
daughter rather than a first-born son (Dahl and Moretti 2004; Morgan,
Lye, and Condran 1988).22

Given Caplan's theory, I think that this should be measured again after 25 years or so, to see what kind of an effect there is then.

Hilary: Wow. I thought that I was prone to thinking and making decisions based on excessively strict and unfeeling economic logic, but you take the cake.

The "fear of losing the first child" is a large, mostly unexpressed factor, IMO. In my particular viewpoint, the twin discoveries of having your first are (a) how much happiness is really possible (a lot!) from having a child, and (b) how excruciatingly vulnerable (the child, and therefore) that happiness is. And if that child dies, there is no "ground state" to return to, just anguish.

The second (and subsequent) child ensure some semblance of such a "ground state" in case of the loss of a child, and the somewhat lesser increase in enjoyment is accompanied by not only a lesser increase in vulnerability of that happiness, but a decrease in the catastrophic vulnerability of that overall happiness.

This was probably more frankly expressed (or at least considered) in a more agrarian society, where children actually brought an economic benefit, coupled with higher accidental death rates. But it still holds.

In comparing identical twins, Kohler found that mothers with one child are about 20 percent happier than their childless counterparts

Since children are not allocated randomly this doesn't necessarily demonstrate what it wants to. Although this is a creative control, twins are still not the same person (nonshared environment, etc). Perhaps the depressive twin would have become even more depressed if she had a child. Perhaps the happy twin would be even happier if she didn't have her child.

Did the depressive twin plan on having a child, and couldn't find a mate? Or did the depressive twin think she didn't want children and it turned out she actually did?

Did the happy twin want a child and then have one? Or did she not want a child, accidently conceive* and was happier for it?

* I suppose we'd have to look at women who do not believe in abortion/adoption for this.

"The argument for more than one kid, in this view, would rest on risk-aversion and the chance that one kid might die or not work out so well."

I would implore anyone capable of that line of reasoning in this day and age not to procreate. This statement is a sure sign of defective emotional intelligence - something best not passed onto one child, much less two.

Yersinia pestis > fleas (so sue me)

The question on the survey was "How satisfied are you with your life, all things considered?" I don't see that translating into "How happy are you?" More kids means more strain on resources (time, money, energy) and more opportunities for women in particular to see where they are falling short, in terms of juggling motherhood, marriage, work, etc. So, sure, I can see a dip in satisfaction. But happiness is much less tangible, especially (and I'll sound maudlin here) the happiness kids bring when, as an earlier commenter noted, you really are a "kid person". My house is a mess, my checkbook is unbalanced, and I need more sleep. I'm not satisfied with this state of things. But I'm happier than I've ever been.

I have an older brother. Having an sibling doesn't gaurantee anything. We haven't talked in 2 years. Besides, he lives half way across the country.

When I hear arguments such as "there is no guarantee siblings will be close /I have a brother and we haven't spoken in years" I just want to cry - this is how bad the logic is. First, there is no guarantee you will cross the street alive (the proverbial bus). Second, if you and your brother have not talked in years, you were most probably raised by parents who did not value closeness to begin with. Too bad for you. I cannot imagine any siblings who grew up sharing a room, giggling at night before going to sleep, and just building childhood memories together ...who would end up not talking to each other for years. Some parents simply rub off their distanced, cold manner onto their children. In that case, yes, the sibling trick is wortless, at best a drain on resources. Otherwise, a sibling relationship will most likely remain the strongest and most authentic tie one has (besides that with the spouse, though sometimes it can be superior to the one with the spuse). In an increasingly mobile, self-centered, community-devoid world, I dare your only-kid to count on "friends" to fill his/her "close relationship" needs. Or wish him/her a spouse who will fill ALL of their needs, at ALL times. Wait. There is no such spouse.
Two children is ideal in the western world. Contemporary populations know it instinctively and this is exactly why most people consciously choose to have two children.

If my husband and I had decided to only have one child we would never have had the priveledge of knowing our second, third and soon to be fourth child. I thank god every day for all my children. I personally feel that parents who have more children learn not to sweat the small stuff and really learn to focus on what is important in life. Sure my oldest son may have had to learn to share and cooperate and to pitch in. And I guess he has had to accept that the world does not revolve around him but he also has constant companionship and has the oppurtunity to be a big brother, a mentor an example which by the way gives him a real sense of accomplishment and pride. Sure they fight and there are times where they must compromise which for a child is difficult but the majority of the time they play and share. It is wonderful to watch. As for me, I am happier now than I have ever been in my life. I am more organized, more focused, more effective and I truly enjoy all my children. I am less selfish and more giving. I am a better parent and a more commited partner. A larger family requires that a husband and wife really learn to cooperate and to share the responsiblity of parenting more equally which only benefits the children. I think it also strengthens the bond between a man and women. Sure more kids means more work but it also means more love, more hugs, more kisses, more first smiles, etc. To see each child develop this distinct personality. The idea that a parent with only one child is happier is ridiculous. I personally feel sorry for both kids with no siblings and parents who only have one child.

I am sure there are people with lots of syblings who were miserable as well as kids without syblings who were and are miserable. I think that the happiness of kids and parents has less to do with number of children in the family and more to do with the dynamics of that family. In fact, many of the mother's I know who only have one child always seem overwhelmed.

I don't like this. I grew up with a brother and sister and they are my best friends. I can't even imagine life without them. Being an only child would have been boring and lonely for me. My best friend in elementary school was an only child and she always wanted siblings so she use to always hang out with me and mine. As far as I know, my mother says she was just as happy having her first, second, and third child. She also says she has enjoyed every moment of raising us individually. I don't think there was ever a time where I felt like I didn't have enough attention and I'm attending an excellent university. I also have lots of friends who get along with their siblings!

If every couple on earth followed the advice of having just one child the human race would disappear from the earth in 32 generations.

In as little as 22 generations with a breeding population the size of 2861 people on the earth it would probably be two late to repopulate with out genetic engineering.

I think that only children are a lot better adjusted than two siblings, especially when they are they same gender(Cain and Abel)to much competition. I find that three and more children seem to do better, and grow up liking there siblings rather than hating them or in constant competition. I happen to be an only child and have plenty of issues, but I don't constantly find myself in competition w/ my friends and peers. My mother had a same gender sibling(my wonderful Aunt Mindy) and barely talk and have been in constant competition there hole lives. My father and his brother who is older haven't talked in twenty or thirty years because competition.
That's why I go back to Cain and Abel. So you tell me who is better adjusted?

I want to be a mother someday. And I plan to have more than one child, not necessarily for MY benefit but for my childrens. I have 3 siblings and could not IMAGINE life without them. They have helped me in so many ways. They are a support system in my adult life. And family parties would not be as fun if I were the only child, regardless of "attentioN" being lessened.

I think all children need a playmate. The friends of mine that are only children...are some of the LONLIEST people i know. They rely on friends for everything social, but friends have their own lives. FAMILY is more permanent.

I have 1 brother 2 sisters... woundn't trade the jerks for the world!

I have three kids, and I think this is the perfect number for me. I got married at 23 to my boyfriend of one year (I know, big mistake) whom I met at Yale. We thought we had a great relationship, but our marriage only lasted two years. Our divorce was finalized the day after my 25th birthday. For the next few years, I focused on my career. I even thought I wanted to adopt, but the birth mother backed out at the very last moment. Now I realize how immature I was. At 26, I met my future husband. This time I took it slower. We married when I was 28. He was 38. A year later, I gave birth to our son, Will. Two years after that, our daughter Audrey was born. We were happily married for the next years. Our kids were 17 and 15 at the time of our divorce. He and I remain close friends, and I'm sure our kids are thankful for that. Immediately after our divorce, I met the man who would become my third husband. Surprise, Surprise, I was pregnant! At first I was shocked but then I became very grateful for such a lovely surprise. Ella is now 1, Audrey is 17, and Will is a 19 year-old freshman at Yale. We live in New York and I'm so thankful for how far I've come. I think my current husband and I will be together forever.

Wow! Quite an interesting opinion. I am not quite sure how and where these "studies" are done. When I was pregnant with my second child I did have doubts that I could love another person like I loved my first but within seconds of giving birth I no longer worried about that and I didn't worry about that at all when I was pregnant with my third. I currently have three and am not done. Each child has brought not only increased happiness but an increased ability to love. I grew up with 4 other sibling and my husband grew up in a family of 7 and we both loved and still love the friends (and during the teenage years the sworn enemies) are siblings are. We are who we are because of our brave parents and our siblings. Happiness comes from healthy family life and the more the merrier (within the parents mental capacity of course)!


Another thought on siblings...
I have 3 older siblings. We are not in touch. One lives 1/4 mile down the road. Awkward...You might say I was the straw that broke the camel's back. The oldest is 20 years older than I, then 18 years older & then 14. My mother was returning to school with grants when she conceived. She blamed me ever after for ruining her life. My parents divorced not long after my entrance. I had a miserable existence for the first 18 years of my life. Now 23, I have my own family & am certain I do not wish to follow in their footsteps because the number of children is very personal but no child should ever feel unwanted or unwelcome upon arrival.


This is a very interesting study, but I find it pretty hard to believe. I personally think it just depends on the person. I agree that having a second child can make a parent more frustrated, but deep down inside they're really happy that they have another family member around to keep them company.

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