Can’t live with them, can’t live without them…but in my experience, it’s mostly can’t live without them. I have one little sister, and we’re incredibly different. Our relationship has always been complex, but I love her to death and she understands me in a way few other people do. Sibling relationships are unlike any other relationship you’ll have in life. You have the same genes and the same upbringing; coupled with sibling rivalry, which is at times at odds with how protective many people are of their siblings—we share a unique bond with our brothers and sisters, no matter how much they annoy us. Fictional sibling relationships are no exception to the complexities and richness of these relationships. They’re some of my favorite relationships to write, because they’re so nuanced and so deep. But they can also be hard to get right, especially for those who don’t have siblings themselves. Here are a few tips for writing realistic brothers and sisters…
Siblings’ behavior towards each other varies wildly.
This is probably pretty obvious, but it’s something to really think about as far as relationship development. Are your siblings close? Are they affectionate? Do they have any issues or resentments? No two sibling relationships are alike, and how people interact with their brothers and sisters varies family to family and across cultures. Sibling behavior also really varies even in the context of one “siblingship” from love to hate to everything in between. It would take a long time to explain all the nuances of my relationship with my sister, but in summary—two strong personalities + almost two decades cohabitation + lengthy times apart + loyalty + resentment + competition + deep understanding + nature + nurture + worry + lots of love + to be honest you really frustrate me Bail Bonds = a pretty normal sibling relationship. There’s a lot at play, probably moreso than any other relationship other than maybe parent / child. And we can turn on a dime with our siblings—we go from fighting to joking around very quickly, and vice versa. Sometimes fights turn into fits of laughter. One time my sister and I were fighting pretty intensely but then I smeared yogurt in her face and we basically got into a food fight and everything was 👌🏻. Very typical sisterly behavior.
We don’t call each other “sis” or “bro” unless we’re kidding.
I’ve seen this multiple times in poorly written fiction, but it’s not something siblings actually do. We do, however, have weird nicknames for each other. I refer to my sister Bailey as Bail Bonds. My best friend calls her sister “Sistur” (Pronounced “sistuhrr”). Sibling nicknames are frequently a little odd. A lot of sibling behavior is a little odd, partially because…
Siblings (if they’re close) usually have tons of inside jokes.
It can sometimes seem as though siblings have their own language. Most brothers and sisters will have at least a few jokes or weird little references only they get. Just a few examples of how these inside jokes could be referenced or reflected in writing—siblings might use made up words and expressions with each other (even as adults), randomly insert obscure movie / TV quotes into conversation, or refer to a certain heavily discussed shared memory simply as “the __ story” (ie. the hat story). Siblings also tend to make fun of each other. How and how often varies, of course, based on the siblingship. And if your fictional sibs are estranged or particularly stilted with one another, they may not joke around much if at all. But for the most part, siblings do lovingly (or not so lovingly) poke fun at each other. Parents also tend to be a popular subject of sibling discussion and occasionally ridicule.
We gossip about our family members.
This is especially true in big families, but even in small ones—siblings are likely the only people you can really talk about your family with who actually fully know what you’re talking about. And since humans are pretty crazy in general, family life can be a beautiful shitshow. You might have your fictional siblings talking about other family members, or simply dealing with them together. Caring for aging parents, or coping with a parent’s death can be an interesting thing from a sibling relationship perspective, because these events can either bring brothers and sisters together, or cause significant tension (I’ve seen this first hand a lot). In general, think about how your siblings’ relationships with each other relate to their relationships with other family members.
Age difference matters. A lot.
This is a big one, possibly the biggest determinant of how siblings will relate to each other. If there’s more than a seven or eight year age gap, it’s likely the relationship will be sort of a combination of siblings and parent-child. There will often be far less fighting in childhood, sometimes carrying over into adulthood. A twenty-year-old just isn’t as apt to fight with a five-year-old as they would be another young adult. That’s not to say they won’t fight, especially when the older sibling is a teenager. There might be tension as the younger sibling grows up, over the older sibling being bossy or treating the younger like a child. But it’s different. If the older sibling moves away from home early in the younger’s life, the relationship may be more distant (or not—there’s as much variety in wide age gap sibling relationships as there is in those only a few years apart). If the older sibling was around a lot during the younger’s childhood, they may have filled more of a caregiving role. Siblings close in age, especially very close in age, tend to be much more competitive with each other. In general, the less of an age difference there is, the more likely siblings are to view each other as equals.
Older siblings often have very different experiences than younger siblings.
Birth order and age gaps affect not only sibling relationships, but the relationships each sibling has with their parents. Almost anybody with siblings knows this, but it’s good to work it into fictional siblingships in some way. Older siblings are often held to higher standards than younger ones. They may be expected to help care for their younger brothers and sisters. It’s also likely that their parents were stricter or “more careful” with them than they were with their younger children. For example, my sister was allowed to watch most PG-13 movies when she was under ten even though I hadn’t been allowed to, mostly because it was just easier for my parents to let her watch what I was watching. Younger siblings may be more precocious than older ones as a result. Older brothers and sisters also tend to let younger ones watch movies or listen to music their parents would not, and at least in my experience swear in front of them quite a bit. Older siblings, especially ones of the same gender, are also often relied on for information about topics (like sex or puberty) that the younger may feel uncomfortable discussing with their parents.
We take each other’s stuff (especially sisters), which leads to issues. Although sometimes we do willingly share clothes / products / etc.
It would be highly realistic for a character to look everywhere for a particular item then finally find it in their sister’s room. Also realistic for a character to stealthily creep into their sibling’s room to steal something, and possibly find their favorite shirt hanging in the closet while they’re there.
Comfort level is one of the biggest factors in developing unique sibling relationships.
As is the case with any relationship, how comfortable two people are with each other strongly affects how they interact. There tends to be a high level of comfort in sibling relationships, but not always, and the degree to which this is true varies. Are your fictional siblings comfortable being their truest, grossest selves around each other? Are they comfortable talking about personal subjects? Some siblings (usually siblings of the same gender) would think nothing of being naked in front of each other, and I know sisters who literally pop each other’s zits. I also know siblings that aren’t even comfortable saying “I love you” to each other. People are all over the map with their brothers and sisters, and because comfort level in sibling relationships is something underlying a lot of variations in sibling behavior, it’s a question that needs to be answered when crafting a fictional siblingship.
Twin telepathy is, apparently, an actual thing.
The mental bond between twins is said to be unlike any other connection between two people, bordering on supernatural. I’m quite open minded to the paranormal, but even I used to dismiss the idea of twins communicating telepathically; turns out it’s very likely a thing, supported not only by anecdotal evidence, but empirical research. There have been many psychological studies over the past fifty years which suggest that twins, especially identical twins, are capable of reading each other’s minds, at least in some sense. Many of these studies (and anecdotal evidence) involve one twin sensing when the other is in danger or in pain. So including this in a generally realistic story would not be ridiculous by any means. In general, twins are likely to be incredibly similar as far as personality, mannerisms, even interests. Sometimes eerily so—the well-known story of the Jim Twins truly makes one wonder about the power of genetic inheritance (and possibly of twin telepathy). However, twins are also individuals, and in some instances they may be very different from one another. My aunt and uncle are twins, and while they are close, in many ways they’re opposites. Regardless of what type of relationship your fictional twins have, being a twin is something that has a heavy effect on one’s life, and oftentimes twins are close in a way that eclipses most other siblingships. Twins can also be pretty creepy in fiction, and there’s plenty to be done with “the twin connection” in the context of a fantasy, sci-fi, or horror story. Jane and Jennifer Gibbons are a good real life example of weird, unnerving twin behavior. Plenty of fodder for a story there.
Consider giving them some shared traits, but don’t make your fictional siblings too similar.
Most siblings do have quite a bit in common due to similar genes and upbringing, but exactly what or how much they have in common varies a lot. Many, MANY siblings seem, in most ways, as different as humanly possible. This is the case with me and my sister, my best friend and her sister, and many other siblings I know. But there are still similarities. Even in siblings who are incredibly different from each other, there will likely be shared mannerisms, expressions, or likes and dislikes. It’s also common for siblings, different as they may be from each other in personality, to have some overlapping core values and odd quirks. For example—my sister and I are like night and day in most ways. She’s reserved, self-reliant, private to a fault, decidedly nonjudgmental, and generally pretty professional as far as her lifestyle and appearance. I, on the other hand, am incredibly expressive and needy, make fun of people for everything, and am far more “alternative” in the way I live my life. But we’re both liberal academic types and we both pronounce the word “tourist” incorrectly (tuuurist), because our parents are liberal academic types, and my father doesn’t know how to say tourist. These are just a few random traits of ours, but you can see the underlying principle. Siblings always have differences and similarities, and oftentimes the similarities found in siblings that don’t have a ton in common as far as personality go back to shared upbringing. Things like core values, manner of speaking, and behavioral idiosyncrasies.
They’re often quite protective, especially of younger siblings.
No matter how much two siblings fight or how brutally they ridicule each other, when somebody outside the family is unkind to one of them, it’s highly likely that person’s sibling will absolutely flip shit. It’s a classic trope—nobody can pick on your little brother / sister except you. It’s both realistic and lends itself really, really well to building strong characters and siblingships. Readers like to see characters protecting the people they love. If you want to make a bad guy more sympathetic, give him a little sister he loves, and show what happens when someone tries to hurt her. Of course, some siblings are more protective than others. But in my experience, protectiveness is one of the most consistent traits of sibling relationships, and I suggest using it in some way to develop your fictional siblingship.
Sibling relationships are as diverse as people are. They’re also unique from all other close relationships, and can be hard to pin down on paper. So if you’re struggling to develop the bond between your character and their brother or sister, the best thing you can do is look to real life siblings for inspiration. If you can’t come up with something for your characters to fight about, or are having trouble choosing what odd little shared traits they inherited from their parents, just take notes on real families. Good art imitates life. 👯♀️