Why are brothers and sisters so annoying?

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On this show, we take questions from curious kids just like you, and we find answers. Today we're talking about a very special family relationship. Potentially, one of the longest relationships some of you will ever have in your lifetime.

The sibling relationship.

That's right. Today, we're talking about brothers and sisters and all the different kinds of siblings you might have. Love them, or hate them, they can be an integral part of your early life, and shape who you become.

Not everyone has a sibling, and that's great. But in the United States, 80% of people have at least one. And while there's a lot of focus on the influence parents have on who we become, studies suggest siblings can have even more of an impact on our development.

“But before we dig into that, first, a very important question.”

Hi, I'm Taylor, and I'm lifelong Malvin, and how brothers and sisters tend to brothers and sisters. Your brothers and sisters are your siblings, and siblings are children in the same family who share at least one parent. So you get your siblings when your parent or parents decide to add you or another child to the family.

Sometimes that's through birth or adoption. You can also have siblings that you only share one parent with. Sometimes people call this a half sibling, which is kind of funny because they're definitely a full person. And you can get step siblings if one of your parents marries someone who already has kids.

Some families care for kids temporarily through foster care or other arrangements, and those kids can also be your siblings, even if they only live with you for a short time. There are a lot of different kinds of families, and so there are actually a lot of ways to get a sibling. Research shows, though, whether you're sibling is your step, half or full sibling, they

can still have an impact on your development. Interestingly enough, most studies of sibling relationships don't even differentiate between the kinds of siblings. I'm Charlotte, and I'm five years old. I love it.

I love it. I'm Terry O'Kenna.

“And my question is, why do fathers and sisters look a lot alike?”

Sometimes siblings look a lot alike, and sometimes they don't look alike at all. Sometimes you look alike because you share genetic material with your siblings. You get half your genes from a male biological parent and half from a female, but the genes you get are randomly assigned, so siblings can get different combinations. And some traits are more heritable, more easily passed down than others.

There are also environmental influences, both in your genetics and in how you choose to look. Maybe you and your siblings dress similarly, or make the same facial expressions, or say the same kind of things because you live together. So your similarities are not just genetic, and sometimes we try our absolute hardest to

look and behave nothing like our siblings. So you and your siblings might look a lot alike, or you might look very different, whether you share DNA or not. When I was a kid, people used to see me out with my stepfather, and they'd sometimes stop us and tell us how much we looked alike.

We always smiled and said, "Thank you," but then we kind of giggle the little bit afterwards,

because we weren't biologically related at all, but we did spend a lot of time together when I was a kid, so it kind of makes sense that we would look alike, and your genetics certainly don't define how you feel about your family, or how much they love you. Beyond the story of how you got your siblings, or whether or not you look alike, your siblings can have a big impact on who you become.

An author, we know, has spent a lot of time thinking about and researching why that is. So we called her up to talk a little bit about what she's learned. Susan Dominus writes for The New York Times Magazine, and one of her books is called "The Family Dynamic." I actually started off thinking about how to write a book about how parents help their

I was really interested in parents who encouraged their kids to think they could change the world.

When I started reporting the book, when I was hearing from these incredible siblings from

families like this, although they talked about their parents, they also talked about the way their siblings helped them get to the point that they were trying to reach. And I realized that that was kind of an underappreciated piece of the puzzle in general when people think about how people become who they are.

“And what did you find from the families that you interviewed?”

Well, I think I found often that the parents were the ones who were maybe setting a tone in the family, and setting maybe they were inspiring people themselves, and some not necessarily famous way, but a way that was really meaningful to the kids. You know, maybe they had immigrated from a farm, a country overseas, and had built new lives.

So their kids could have better opportunities, or maybe they had overcome racial stereotypes

in order to succeed in at times where the world was not really conspiring to help them do that. But the siblings that turned out were often very helpful in giving logistical advice and pointing them in their right directions. And older siblings can really guide the way for younger siblings because they understand

how the school works. They've looked at their friends and seen what worked for them, and they can pass it information down, and sometimes kids, especially teenagers, would much rather have advice from a sibling, even a sibling that they sometimes fight with. They'd still rather have that advice come from a sibling than a parent, because teenagers

really don't like to do what their parents want them to do a lot of the time. Research into siblings backs up what Susan Dominus found in her reporting. siblings are family, but they're also kind of like a peer or friend relationship. You learn how to get along with people by learning how to get along with your sibling,

with the safety that they'll always still be your sibling.

That doesn't necessarily mean it's easy. We have a question from Julia. I am nine years old.

“I live in Taragona, Spain, and my question is, why do I fight with my sister if I love her?”

I think that sibling tensions are very, very natural, and you know, I don't know this is the kind of thing you can prove, but evolutionary biologists would say it really all comes down to resources or a feeling of resources. It's hard to avoid the feeling that, you know, love is a pie, and that the bigger your sister slices, that means the smaller yours is, but one of my favorite short story collections

is called Love is not a pie, meaning it doesn't deplete, you know, if you give some to one person, it doesn't mean there's not enough for the other person, and so I think part of getting older is realizing that there's enough to go around, but I also think that siblings are trying to differentiate from each other, and that also it's just unfortunate for siblings that people tend to compare them, and I think that puts people, a kid's

especially in an uncomfortable place sometimes. I love that Susan mentioned, the short story, Love is not a pie. It's one of my favorite short stories written for adults, but also the author Amy Bloom was on our show several years ago, in an episode called How Does It Feel When Your Family Changes. You might enjoy listening to that one, and research has shown that having a younger sibling

teaches older siblings things like empathy, that's the ability to understand how someone else might be feeling, and to work on social skills like sharing and playing.

“Coming up, if having siblings is so great, why do they drive you nuts?”

This is, but why, from Vermont Public, I'm Jane Lindholm, we're learning about brothers and sisters and siblings today. We're speaking with Susan Dominus, she wrote a book about families where multiple siblings did big things as teenagers and adults. She wanted to know what was happening in those families that led to the children becoming

what are sometimes called high achievers. The book is called The Family Dynamic. It's a book written for adults, but Susan likes thinking about and talking with kids too. So she was excited to answer your questions. Here's one we got from a lot of you.

I'm Nick or I'm 10 years old, and I'm living Columbia, close to Bogota. Why don't siblings get along perfectly? Hi, my name is Mary. I'm eight years old, and I live in Gary, Indiana, and my question is, why do siblings fight a lot?

Hi, my name is Phoebe, I live in Barbados, I have six years old, why don't those sisters and about just so annoying, and goodbye? My name is Ruby, I'm seven years old, I live in Fair Oak's California, my question is why

I think it is a little bit at just a question of proximity.

You know what I mean? Even roommates who live together often, they start to get on each other's nerves. There's just so many little choices and tasks and interactions that happen over the course of the day. I think with siblings that's even more complicated because your sibling is just enough

“like you, maybe, that you think that you should get along perfectly, but siblings actually”

are also just different enough that they're going to have different points of view, different taste, different personalities. And I think that sometimes we feel what's known as cognitive dissonance when we look at someone and say, "You're my sibling, you might even look like me. Why is that you of all people don't see things the way that I do?"

But I think that can be really frustrating and surprising to us, maybe.

Your siblings are learning to have a relationship with their peers through their relationship with you and any other siblings. Often that means testing out new strategies, whether they realize that's what they're doing or not. So maybe they're making an annoying noise and waiting to see your reaction.

If you think it's funny, maybe they'll try that noise with their friends. If you think it's annoying, well, maybe they'll learn. Of course, it's also totally possible. They're just doing it to annoy you.

“And if you show your annoyed, they might do it again.”

Do sibling relationships and the effect of having a sibling tend to flow from the oldest

sibling down to the youngest as the oldest sibling always set the tone or always create

the conflict or always create the support to help another sibling succeed or can it be mixed depending on where you fall in the family. Even at a young age, we do know that there is something called a sibling spillover effect. What that finds is that when one sibling starts doing better in school, the other siblings do as well, and there's a complicated way they were able to figure out that it's not

because of Heather parenting has been changed or because of some genetic overlap. I won't bore you with the details, but scientists were very clever about how to do a study that separated that out. So they can really see that it, no, no, it's the way that the sibling is behaving. That's changing the other sibling.

And those effects can actually work in both directions. They can go older to younger, but also younger to older. I think even the older you get, the less the age of the siblings matters. You know, when everybody's out there in the world and they're doing their own thing, that's when you really see often a kind of network effect of siblings who are helping each other,

because when you're 36 years old, it doesn't matter if you're 32 year old sister is the person who makes that introduction for you or gives you advice. Does that work for things like musical instruments and playing sports, too, or just in school? There's not tons of research about that, but I would assume it works for all kinds of things. There's like a fun fact, there are some researchers who've been trying to make the case

that younger siblings are overrepresented actually in sports. And that's because of this idea of differentiation, because the oldest sibling for various

“reasons, maybe because the parents put the most pressure on them, that's what some research”

suggests. But the oldest siblings tend to be the most academically strong. And so then younger siblings think, well, I'm not going to be able to own that. So I'm going to instead throw myself into sports. It's not like we think that they're biologically more athletic for some reason.

It just seems to be a choice in how they invest their energy. Parents have an effect on cognitive development, brain development, of their oldest kids, because they often spend the most one-on-one time with their eldest child. There are no other kids to compete for their attention. But those benefits are then passed down to the younger children by that eldest child,

especially around literacy, reading. Older siblings looking at books with their younger siblings can help them learn to read. And the eldest own reading ability is improved by spending that time reading with their younger siblings. But are there limits to the sibling relationship?

My name is Akira, and I'm a six-year-old, and I'm from Japan. And my question is, "Can my sister be my best friend?" I mean, when that works, it's the greatest thing ever. I can tell you that my sister is probably my best friend, and we are really different. In fact, we look so different that when we were little, somebody once put my sister in

one room and me in another room, and these kids grilled us on what our father's middle name was and things like that, because they couldn't believe we were sisters. And we have fought plenty over the years, and I'll tell you a little secret.

she was the person plunked into my family along with me.

And in fact, I even moved around the corner from my sister when I was trying to figure out where to land with my husband before we even had a family. Simbling dynamics tend to change as kids get older. And the kids who are older start to allow younger siblings more power in the relationship.

“That shift can be messy, but it's important to developing the relationship that will”

exist throughout your adulthood. In Susan's book, she wrote about how siblings will often push each other to be better people. They can compete with each other and make each other better. So for example, I wrote about the Hall of Field family, which was a sibling of civil rights

activists who came out of Tallahassee, Florida, at a time when it was really hard to be a young black person in this country. One of the siblings, when she was only 16 years old, decided that she was going to be one of the only three kids who were black, who desegregated the biggest best high school in the capital of Florida, which was the last of all of the states apparently to integrate.

“Integration was bringing together black and white students into the same schools.”

This was happening in the 1950s and 1960s. Students were educated separately before that because of racism and racist laws. And her older brother Bishop said he looked at her and thought, "Wow, she's really set the bar really high." And now I want to honor that and live up to it.

And when he got to law school at Harvard, he started the black law students association,

which was one of the first kind of groups like that on any law school.

And it was hugely influential. He helped bring the first black law professors to Harvard law school, then other schools followed suit. And so there's all kinds of ways that siblings can inspire each other and really go on to do great things.

So, what if you don't have a sibling? It's funny. I just had dinner last night with a young woman who is an only child and she was telling me that she kind of instinctively became friendly with lots of lots of young women, her age, and almost would describe many of those friends like a sister.

“And I think in some ways, to have a friend who's like a sister, but with all the baggage”

of actually being a sister, hey, that's like, that's maybe even the best case scenario. There are really special things about having a sibling, but there are also really special things about being an only child and having your parents undivided attention and not ever being compared to anybody else, not having to deal with the day-to-day irritations of maybe sharing a room or sharing a bathroom, waiting your turn.

I think there are a lot of tensions in life that are very painful from which you're really completely liberated. Whatever your relationship with your siblings or if you are the only child in your family, your relationships with your family shape your future in important ways. There's no wrong or right way to have a family.

That's it for this episode.

As always, if you have a question about anything, have an adult record you asking it on

a smartphone using an app like voice memos, then have your adult email the file to question questions at ButYKids.org. Our show is produced by Sarah Baker, Melody Bodet and me, Jane Lindholm, at Vermont Public and Distributed by PRX. Our video producer is Joey Palombo and our theme music is by Luke Reynolds.

If you like our show, please have your adults help you give us a thumbs up or a review on whatever podcast platform you use to listen to us. It helps other kids and families find us. We'll be back in two weeks with an all new episode. Until then, stay curious.