Emily Oster

10 min Read Emily Oster

Halfway through the first week of Christmas break, and I cannot be the only person whose house has some sibling conflict. Someone put a toe into another person’s room. Someone peed on the toilet seat and then just left it. Certain items were touched without permission.

Conflict between siblings can be especially unnerving since it happens so fast. One minute, they’re playing Candyland. The next, someone’s been hit with the board. Physical boundaries are routinely ignored. Play wrestling turns into real wrestling turns into mixed martial arts in the amount of time it takes you to put out the trash. Moments of conflict follow moments of camaraderie so quickly you get whiplash.

How can we better manage this? Or should we?

It feels important for a number of reasons. One is that kids fighting is unpleasant and disruptive. But the second is that, for a lot of us, we want our kids to be friends now so they’ll be friends as adults. For many people with siblings, those adult relationships are very important — they’re different from almost any other relationships you have — and we may want to nurture good versions of these for our own kids. It can feel like there is a direct link between peaceful Candyland play and adult cohesion.

This link between childhood and adulthood is at best a bit more complicated. Sibling conflict among children is the norm. Jessica Grose had a great piece on its overall psychology earlier this year. There are reasons why rivalry makes sense on an evolutionary level. That doesn’t mean we cannot work to mitigate it, but it highlights that it’s a typical part of childhood and doesn’t necessarily have a direct line to adult friendships. In my own case, my mother saved our New Year’s resolutions from childhood, and for about a decade mine was to be nicer to my brother John (sample: “I resolve to be nicer to John even though he is really annoying”). Yet as adults we are very close (even though sometimes he is really annoying. JK!).

This isn’t to say that the relationships you cultivate among your children can’t translate into their adult relationships, just that they do not necessarily do that. In the end, it is likely to be more productive to focus on addressing the issues you see now, since that’s really what you can control.

In thinking about this, I of course started with the data. It may not surprise you to find there isn’t a lot of detailed quantitative research on this. No secret formula that randomized trials have shown will work with all siblings. There’s research, but it’s more theoretical, anecdotal; stories about what has worked for some people rather than hard data measurements.

For people who like numbers, there is a temptation to just dismiss this work. But that throws away valuable information! We can use these data, but we need to use them a little differently. Specifically, when confronted with this problem, I found myself using the research/data/books in the same way I’d use advice from family and friends. I incorporated it and reflected on it. I thought about what might work for my family. And then I self-experimented.

In that vein, here’s a short dive into some of the research-based advice you’ll get on siblings, and a note on how to self-experiment.

Advice on sibling rivalry from your research friends 

The research-type literature on siblings isn’t quite like the literature on, say, breastfeeding or charter schools. There are only a few cases in which we see data on what works, with detailed statistical follow-up. Instead, there are many papers that contain informed discussion, based on work with families or on observing family dynamics. They talk about what works in these settings and try to draw some broader conclusions about good practices.

A common refrain (see, e.g., this paper) is to avoid favoritism or comparisons between children (easier said than done, sometimes). This advice would come down to not saying, for example, “See how well Tommy uses a fork? Why can’t you use a fork like Tommy?” Instead you could say, “Please use a fork.”

Differential treatment by parents is also associated with more sibling aggression. This may come in the form of favoritism, or a sense that one child is being held to a different standard. One thing that’s tricky is that children are very attuned to fairness, and they may perceive differential treatment when it’s not intended. I reflected on this lesson the other day when my children insisted on watching while I used the kitchen scale to weigh out exactly the same amount of Chex Mix (29 grams) into each of their snack bags. Neither of them ate it, FYI.

In the extreme, sibling conflict can lead to sibling bullying. A review of data on this reveals bullying to be more common in households with boys and those with more children or children very close in age. Parental involvement and parental “warmth” were also associated with less bullying, although it’s a bit hard to establish causality in that type of setting.

On the slightly more data-oriented side, we have older literature on parental non-interference in fighting. For example, there’s this small study of a few families in which parents were trained to ignore fighting, and later their self-reports indicated less fighting. This might suggest less conflict if parents stay less involved. It is a source of some controversy, with other authors noting that this could cause children to feel their parents are abandoning them to an abusive older sibling.

In reflecting on it, the work on bullying and non-interference feels to me like a case where there is a happy medium. Sometimes you need to leave them alone to work it out. But also, you don’t want your kid to feel like you aren’t going to stand up for them if they need you.

Overall, there was less of this academic literature than I had expected. I did manage to find a paper on armed rivalry in pigs (they use their “8 saber-like teeth” to fight for access to milk) and another paper on sibling rivalry in family business succession. They seemed about equally unrelated to my personal life.

In the end, the most valuable thing I read was Siblings Without Rivalry, a book by the authors of How to Talk So Kids Will Listen & Listen So Kids Will Talk, which I frequently hear people sing the praises of.

I devoured this book in a day, and it really made me think. What’s interesting about it, in line with the overall approach here, is that it isn’t a how-to book. This isn’t “1-2-3 Magic” for sibling cohesion, although the authors do have some more step-by-step advice. Instead, the book is structured to follow a multi-week group counseling session, in which you effectively hear the discussion of each topic, the perspective of various individuals, and then some feedback on their own attempts to address sibling conflict in their homes.

There are a few big-picture ideas I pulled out of the book. One is a reiteration of “don’t compare your kids.” Another, which I hadn’t seen elsewhere, is the idea of “equal is less.” Saying “I love you all the same amount” makes kids feel less special than “I love you because you’re my special Sofie/Anna/Phillip.”

The overarching action from the book, which comes up in many of the examples, is the idea of acknowledging frustration or conflict. When the book discusses fighting, for example, the approach begins with stating the obvious — that everyone seems upset — and going from there. A similar idea comes up in dealing with jealousy over time, fair allocation of stuff, and so on.

This discussion isn’t exhaustive, and if you’re worrying through these issues, you’ll want to investigate a little bit more. It’s worth reading the whole rivalry book, and possibly a few papers. You might even collect advice from the more research-based people online (I like Big Little Feelings, for example, even if I don’t always agree with everything).

The key with a question like this — where the data is kind of limited, more anecdotal, more “what works for some people,” and where your personal child situation is likely to be very specific — is to use it for idea generation. And then implement with your own data-oriented approach.

Self-experimentation

Self-experimentation is precisely what it sounds like: experimenting on yourself. I see it discussed most frequently when people think about their own health/diet/fitness. You’re wondering if dairy makes you bloated? Eliminate for a week and track your bloating, then add it back in. Does coffee after 3 p.m. affect your sleep? Try it for a couple of weeks and track your sleep on your fancy watch. And so on.

It’s not exactly randomized, and it is definitely not double-blind. But the value is that whatever results you get, they’re specific to you. And in a world in which, say, dairy has different bloating effects on different people, it’s probably a lot more valuable to know what happens in this experiment than to see a larger sample of people who are not you. This type of self-experimentation works well when it’s possible to get relatively fast feedback. It wouldn’t be good if you were interested in inventions that make you live longer, obviously.

Sibling conflict gives you frequent feedback. If and when you decide to try making a change, plan a personal experiment. Maybe collect a couple of days of casual data — how many times you had to intervene, how many warnings you gave, how many times one child smacked the other or yelled, “MOOOMMM!!!”

Then implement your plan and track another couple days. Make a little chart, if you are so inclined. This isn’t for publication, so it doesn’t have to have very robust standard deviation. But it’s a way to get a concrete sense of whether your changes are working.

On my end, after reading and thinking, the lesson I took away was the idea of acknowledgment. I now try to say, “I hear you are feeling angry about the balloon” rather than, “Well, OK, let’s fight about this later and now just come and have dinner.” It is so awkward and I feel like an idiot. The other day on the way to school I said, “I hear you are angry that [other sibling] might get a lollipop.” Who says that?

But the thing is, I paid attention to what happened when I tried this, and for one kid in particular, it really seems to work to defuse the situation. Now I’m stuck with it. Should you try this? Maybe! Or there could be another insight that sounds better.

Nothing is going to eliminate sibling conflict, so that cannot be the goal. It’s OK that your kids fight! And there’s no data-based magic bullet to fix it. But a little research-based advice and some self-experimentation can help.

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The list of what not to do while pregnant feels longer than a CVS receipt. At ParentData, we want to empower you to make the right decisions for you. 

What an amazing group of women, and an honor to speak at the #MomsFirstSummit debunking parenting myths. 

What are some pregnancy rules you chose to bend after being empowered by data?

#emilyoster #parentdata #pregnancyproblems #pregnancymyths

The list of what not to do while pregnant feels longer than a CVS receipt. At ParentData, we want to empower you to make the right decisions for you.

What an amazing group of women, and an honor to speak at the #MomsFirstSummit debunking parenting myths.

What are some pregnancy rules you chose to bend after being empowered by data?

#emilyoster #parentdata #pregnancyproblems #pregnancymyths
...

Looking for Memorial Day Weekend plans? Might be the perfect time to give potty training a shot. Potty training is notoriously difficult, and we unfortunately don’t have a lot of evidence-based guidance on what works best. So I asked the ParentData community to fill out a survey and share their knowledge — about 6,000 people responded.

👉Comment “Link” for a DM to an article that summarizes all of the best potty training advice we collected. 

Remember, you are not alone in the potty training struggle! It can be incredibly challenging, so please give yourself some grace.

#emilyoster #parentdata #pottytraining #pottytrainingtips #toddlertips

Looking for Memorial Day Weekend plans? Might be the perfect time to give potty training a shot. Potty training is notoriously difficult, and we unfortunately don’t have a lot of evidence-based guidance on what works best. So I asked the ParentData community to fill out a survey and share their knowledge — about 6,000 people responded.

👉Comment “Link” for a DM to an article that summarizes all of the best potty training advice we collected.

Remember, you are not alone in the potty training struggle! It can be incredibly challenging, so please give yourself some grace.

#emilyoster #parentdata #pottytraining #pottytrainingtips #toddlertips
...

We’re hiring an Associate Editor at ParentData! More details at my link in bio. Please share with the great writers and data-loving people in your network. 📊💻

We’re hiring an Associate Editor at ParentData! More details at my link in bio. Please share with the great writers and data-loving people in your network. 📊💻 ...

Do you brand things a certain way to get your kid to accept it? Like calling carrots “rabbit popsicles”? Or telling them to put on their “super speed socks” in the morning? Share your rebrands in the comments below! You never know who you might be helping out 👇

#emilyoster #funnytweets #relatabletweets #parentingjokes #kidssaythedarndestthings

Do you brand things a certain way to get your kid to accept it? Like calling carrots “rabbit popsicles”? Or telling them to put on their “super speed socks” in the morning? Share your rebrands in the comments below! You never know who you might be helping out 👇

#emilyoster #funnytweets #relatabletweets #parentingjokes #kidssaythedarndestthings
...

Have you ever panic-googled a parenting question when everyone else is asleep? If so, you’re not alone. 

Today is the first episode of a new biweekly series on my podcast: Late-Night Panic Google. On these mini-episodes, you’ll hear from some familiar names about the questions keeping them up at night, and how data can help. First up: @claireholt!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #emilyoster #claireholt #parentingstruggles #parentingtips #latenightpanicgoogle

Have you ever panic-googled a parenting question when everyone else is asleep? If so, you’re not alone.

Today is the first episode of a new biweekly series on my podcast: Late-Night Panic Google. On these mini-episodes, you’ll hear from some familiar names about the questions keeping them up at night, and how data can help. First up: @claireholt!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #emilyoster #claireholt #parentingstruggles #parentingtips #latenightpanicgoogle
...

Sun safety is a must for all ages, especially babies! Here are my tips for keeping your littlest ones protected in the sunshine:
☀️ Most importantly, limit their time out in hot weather. (They get hotter than you do!)
☀️ Keep them in the shade as much as possible when you’re out.
☀️ Long-sleeve but lightweight clothing is your friend, especially on the beach, where even in the shade you can get sunlight reflecting off different surfaces.
☀️ If you want to add a little sunscreen on their hands and feet? Go for it! But be mindful as baby skin tends to more prone to irritation.

Comment “Link” for a DM to an article on the data around sun and heat exposure for babies.

#sunsafety #babysunscreen #babyhealth #parentdata #emilyoster

Sun safety is a must for all ages, especially babies! Here are my tips for keeping your littlest ones protected in the sunshine:
☀️ Most importantly, limit their time out in hot weather. (They get hotter than you do!)
☀️ Keep them in the shade as much as possible when you’re out.
☀️ Long-sleeve but lightweight clothing is your friend, especially on the beach, where even in the shade you can get sunlight reflecting off different surfaces.
☀️ If you want to add a little sunscreen on their hands and feet? Go for it! But be mindful as baby skin tends to more prone to irritation.

Comment “Link” for a DM to an article on the data around sun and heat exposure for babies.

#sunsafety #babysunscreen #babyhealth #parentdata #emilyoster
...

I’m calling on you today to share your story. I know that many of you have experienced complications during pregnancy, birth, or postpartum. It’s not something we want to talk about, but it’s important that we do. Not just for awareness, but to help people going through it feel a little less alone.

That’s why I’m asking you to post a story, photo, or reel this week with #MyUnexpectedStory and tag me. I’ll re-share as many as I can to amplify. Let’s fill our feeds with these important stories and lift each other up. Our voices can create change. And your story matters. 💙

#theunexpected #emilyoster #pregnancycomplications #pregnancystory

I’m calling on you today to share your story. I know that many of you have experienced complications during pregnancy, birth, or postpartum. It’s not something we want to talk about, but it’s important that we do. Not just for awareness, but to help people going through it feel a little less alone.

That’s why I’m asking you to post a story, photo, or reel this week with #MyUnexpectedStory and tag me. I’ll re-share as many as I can to amplify. Let’s fill our feeds with these important stories and lift each other up. Our voices can create change. And your story matters. 💙

#theunexpected #emilyoster #pregnancycomplications #pregnancystory
...

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio!

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio!

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio!

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

Is side sleeping important during pregnancy? Comment “Link” for a DM to an article on whether sleep position affects pregnancy outcomes.

Being pregnant makes you tired, and as time goes by, it gets increasingly hard to get comfortable. You were probably instructed to sleep on your side and not your back, but it turns out that advice is not based on very good data.

We now have much better data on this, and the bulk of the evidence seems to reject the link between sleep position and stillbirth or other negative outcomes. So go ahead and get some sleep however you are most comfortable. 💤

Sources:
📖 #ExpectingBetter pp. 160-163
📈 Robert M. Silver et al., “Prospective Evaluation of Maternal Sleep Position Through 30 Weeks of Gestation and Adverse Pregnancy Outcomes,” Obstetrics and Gynecology 134, no. 4 (2019): 667–76. 

#emilyoster #pregnancy #pregnancytips #sleepingposition #pregnantlife

Is side sleeping important during pregnancy? Comment “Link” for a DM to an article on whether sleep position affects pregnancy outcomes.

Being pregnant makes you tired, and as time goes by, it gets increasingly hard to get comfortable. You were probably instructed to sleep on your side and not your back, but it turns out that advice is not based on very good data.

We now have much better data on this, and the bulk of the evidence seems to reject the link between sleep position and stillbirth or other negative outcomes. So go ahead and get some sleep however you are most comfortable. 💤

Sources:
📖 #ExpectingBetter pp. 160-163
📈 Robert M. Silver et al., “Prospective Evaluation of Maternal Sleep Position Through 30 Weeks of Gestation and Adverse Pregnancy Outcomes,” Obstetrics and Gynecology 134, no. 4 (2019): 667–76.

#emilyoster #pregnancy #pregnancytips #sleepingposition #pregnantlife
...

My new book, “The Unexpected: Navigating Pregnancy During and After Complications” is available for preorder at the link in my bio!

I co-wrote #TheUnexpected with my friend and maternal fetal medicine specialist, Dr. Nathan Fox. The unfortunate reality is that about half of pregnancies include complications such as preeclampsia, miscarriage, preterm birth, and postpartum depression. Because these are things not talked about enough, it can not only be an isolating experience, but it can also make treatment harder to access.

The book lays out the data on recurrence and delves into treatment options shown to lower risk for these conditions in subsequent pregnancies. It also guides you through how to have productive conversations and make shared decisions with your doctor. I hope none of you need this book, but if you do, it’ll be here for you 💛

#pregnancy #pregnancycomplications #pregnancyjourney #preeclampsiaawareness #postpartumjourney #emilyoster

My new book, “The Unexpected: Navigating Pregnancy During and After Complications” is available for preorder at the link in my bio!

I co-wrote #TheUnexpected with my friend and maternal fetal medicine specialist, Dr. Nathan Fox. The unfortunate reality is that about half of pregnancies include complications such as preeclampsia, miscarriage, preterm birth, and postpartum depression. Because these are things not talked about enough, it can not only be an isolating experience, but it can also make treatment harder to access.

The book lays out the data on recurrence and delves into treatment options shown to lower risk for these conditions in subsequent pregnancies. It also guides you through how to have productive conversations and make shared decisions with your doctor. I hope none of you need this book, but if you do, it’ll be here for you 💛

#pregnancy #pregnancycomplications #pregnancyjourney #preeclampsiaawareness #postpartumjourney #emilyoster
...

We are better writers than influencers, I promise. Thanks to our kids for filming our unboxing videos. People make this look way too easy. 

Only two weeks until our book “The Unexpected” is here! Preorder at the link in my bio. 💙

We are better writers than influencers, I promise. Thanks to our kids for filming our unboxing videos. People make this look way too easy.

Only two weeks until our book “The Unexpected” is here! Preorder at the link in my bio. 💙
...