Tuesday, May 7, 2019

The Dynamics of Sibling Relationships

Are you in, or have you ever been had, a sexual or romantic relationship with a sibling? Are you aware of someone who is or has been?

Throughout history, all over the world, regardless of class or other demographics, siblings have done everything from engaged in childhood exploration to having lifelong spousal relationships with each other, but myths about these relationships persist. In a study in the 1970s, ten percent of anonymous college-aged respondents indicated that they had already had consensual sexual contact with a sibling. As they age and have more opportunities, the percentage of sibling who've had sexual contact can only rise. You know people who've been involved, whether you know it or not.

While many places have laws against siblings sharing sex and it is labeled in many places as a taboo, there is clearly a fascination with such relationships that is widespread. some media depictions, such as in the Game of Thrones television series, are very popular and considered by many to be tantalizing. Siblings have been getting together in our stories as long as we've been telling stories, whether those stories have been erotica or not.

What makes people siblings? Genetically, siblings are people who share at least one genetic parent. Sharing one makes them half-siblings. Sharing both would make them full siblings. People can also be siblings by affinity, such as stepsiblings, meaning that each has a parent who married each other, or they were adopted by one or both common parents, or even that that genetically unrelated embryos were donated to and implanted in the same woman. Socially, people can informally be siblings through longtime cohabitation during childhood, even though no formal adoption or marriage legally links them.

Genetic siblings are often, but not always, raised together. Full and half siblings can grow up separately due to age, parental breakups and custody agreements, cuckolding, gamete or embryo donation, adoption, even deportation. For example, a couple might have their first child together at 19 and their last child together at 39. Those children will be full blood siblings, but will be 20 years apart in age, and it could be that the elder sibling has moved away before the youngest is even born. Embryos donated to different parents can be full siblings, raised apart. There are many scenarios in which half siblings are raised apart.

How It Happens

When genetic siblings, whether half or full, are not raised together (having minimal, if any contact from age 7 into puberty), what we call the Westermarck Effect ("Yuck! I can't imagine being with my brother!") is not present. This means there is a significant chance that if they meet or are reunited and their genders and sexual orientations are compatible, there is about a 50% chance at least one of them will experience reunion GSA, whether they are aware of their relation or not. Stepsiblings not raised together are also not going to have the Westermarck Effect and may experience an attraction, but there wouldn't be a genetic component to it in the same way as genetic siblings would have.

Siblings raised together, whether genetically related or not (stepsbilings and adopted siblings may not be closely related), will likely experience the Westermarck Effect, but they might not.

Whether the Westermarck Effect will be present or not, siblings close in age and living together often engage in childhood exploration or experimentation, such as "playing doctor" or "playing house" or "show me yours and I'll show you mine." That is often a matter of proximity, trust, and convenience, as it can be when adolescent siblings do thinks like masturbate in front of each other or engage in sexual acts with each other. When the Westermarck Effect is not present, siblings are much  more likely to engage in siblings-with-benefits arrangements, flings, or ongoing affairs or romances, from puberty throughout life.

Reunion GSA can happen any time from puberty onward as people seek our genetic relatives or encounter them even if they weren't aware they existed.

As for siblings raised together, sometimes things start in childhood or adolescence and continue, even if off an on. Wrestling with each other, teasing, dares, games, and even double dating can lead to more. Especially when and where adolescent sexuality was shamed, nobody would get a "reputation" if they were getting their curiosities and urges satisfied in their own home.

Some might initiate a new dimension to their relationship as adults. Often, but not always, some significant family event creates the conditions that foster this. Siblings might move in together for financial or security reasons or into an inherited home, or to care for an aging or ailing parent or sibling or for one another. Weddings, breakups, divorces, loss of employment, new employment in the same city as a sibling, funerals, family reunions, and other events can bring siblings together in a situation where new opportunities are presented and old crushes are reconsidered. It doesn't always have to be like that; it could be simply that the siblings spend time together and end up doing what comes naturally to them.

Adult siblings have always been able to live together with the blessing of family, neighbors, and the wider culture, whether young, middle aged, or elderly. In some cultures it has been expected that a woman (especially with her father deceased) live in her brother's home until she legally marries.

It shouldn't be surprising that where there is no Westermarck Effect or it is weak, siblings may get together. Studies have shown that most people are attracted to people who look like them, and who looks more like you than a genetic sibling? They may also look and behave like your parent, and the idea that we look for mates like our parent(s) could also be a factor. Even with stepsiblings comes the consideration that we are our parent's child, and our parent was attracted to their parent, so it shouldn't be surprising if we are attracted to a stepsibling. Full genetic siblings or half siblings with a shared genetic mother usually emerged from the same womb, a biological and experiential connection shared with few, if any, others.

Reunited siblings might not even see each other as siblings. But for others, there is an existing bond, trust, and usually opportunities and convenience that can be a very strong mix to foster a sexual dimension to their relationship. Those things can be so strong even in adolescence that siblings might experiment with (or at least in front of) each other against their sexual orientation.


Although many people express disgust at the idea of people they don't even know being sibling lovers, a common fantasy of many people is to have a sexual threesome with twins or other siblings; this involves incestuous aspects, whether the person having the fantasy recognizes that or not. Certainly not always, but sometimes, crushes for a sibling's friend or dating/hooking up with that sibling's friend is a "safe" redirection of what is actually a desire for a sibling, as can be dating/hooking up with someone who closely resembles a sibling. Dislike of a sibling's dates or lovers can be (but isn't always, of course) rooted in the desire to have that sibling to themselves. Dreams of having a sex with or marrying a sibling may be symbolic of something else entirely, or may be an indication of latent desires or attractions.


Due to bigotry, often codified in laws criminalizing their love, most siblings keep their relationships somewhat closeted. A desire to have a family or pressure to marry (or stay married) can mean the siblings are with others ("beards") as spouses, and sometimes those spouses are not informed and consenting to the sibling relationship. Others are aware, and polyamory may be involved, even if it is secret to those outside of the relationships.

Where an affair is being carried on behind a spouse's back, suspicion may be avoided because many people don't think that their spouse would have sex with their sibling. Even if a baby is born from such an affair, it isn't suspicious for the baby to look like one parent and that parent's family but not so much the other parent.

The Results

Some siblings experiment a few times and that's that. Nothing more results.

At the other end of the spectrum is a very powerful connection between them to the point that no other relationship could compare or satisfy on the same level.

In between, there many possibilities, including ongoing "siblings-with-benefits."

There are a couple of countries that will legally marry half siblings, and some countries will allow siblings to be together even as the aren't allowed to marry, but there's much hostility facing siblings lovers.

Just as siblings might get together for the same reasons others get together, consanguinamorous relationships between siblings often have the same difficulties as other relationships, such as quarrels and disagreements, conflicting goals and priorities, jealousy and insecurity. Sometimes, the sexual part of the relationship or even the whole relationship ends.

Unfortunately, getting effective relationship counseling or therapy often isn't an option because of criminalization and a lack of research. Medical care may also be hindered for the same reasons, especially for any children they have together, and since siblings (with the exception of half siblings in a couple of countries) aren't allowed to legally marry, it can mean an estranged parent makes medical decisions for one when the person who is their spouse in every way except under the law isn't allowed.

In addition to the threat of imprisonment in many places, consanguinamorous siblings face discrimination in the workplace and housing, and may lose custody of their children (including children from other relationships) simply because they love each other. Strangely, some people insist that a woman is capable of consenting to go to war, but not to consent to a relationship with a brother or sister. Prejudices often extend to stepsiblings.

Since laws have often assumed heterosexuality, there may be laws in some places, including some US states, where it is now technically legal for same-sex siblings to have sex and marry. Existing laws have intended to deny siblings the right to marry or even be together, but antigay laws that have since been removed used to already prohibit same-sex relationships. If you want to look into this, consult a lawyer (especially a criminal defense or family law attorney) where you live.

These lovers might find it helpful to move where nobody knows of their relation. If they are genetic siblings, having children together can still expose their secret due to DNA tests, and as long as someone from back home hasn't sent a private investigator to follow them, they may find they have the freedom to do simple things like walk hand-in-hand in public and share a quick kiss.

Whether or not sibling lovers move away from family and friends, if they share one or both parents, they are likely to have less extended family than lovers who aren't as closely related.

Siblings who are not involved in the relationship might be envious, or might fear the backlash of bigotry should others come to know about the relationship. On the other hand, polyamorous relationships can and do happen between siblings, even with people who might not be polyamorous in other situations. Parents of involved siblings or children of involved siblings might also have concerns about what will happen should others come to know of the relationship, and many people in such situations don't like to think of their children (no matter how old) or their parents as sexual beings in the first place. Family members may be hostile, even ratting out the lovers to authorities. It's commendable when they are, instead, accepting and supporting, but sometimes all the lovers can hope for is a "don't ask, don't tell" policy in which their family won't interfere as long as things are kept discreet and/or unsaid.

Although these relationships do face much prejudice, socially and legally they are more accepted than intergenerational consanguinamory.

While there are risks and some challenges (mostly due to prejudice), there can be strong benefits to having a romantic and/or sexual relationship with someone with whom one already has so much in common.

In addition to the usual reasons romantic/sexual relationships end, such as incompatibility, some of these relationships drop this form of intimacy because of the bigotry faced ("I want to get married and have a family, and I can't do that with my sibling"), which is a real shame. Some siblings hate each other; it's too bad that siblings who love each other so much would be in any way restrained.

The Way Forward

It should be up to the individuals involved as to whether or not they enter into, or persist, in a romantic or sexual relationship.

Laws and prejudices against these relationships must be changed, and changed sooner rather than later, as people are suffering for no good reason. Lovers, friends, family, and allies should help to make this happen. This will allow more serious research to be conducted, which will make things better for everyone.

In the meantime, lovers should consider what they need to do to protect themselves and each other, and their allies should assist them in those things.

Consenting adults may do things with each other that might disgust a majority of other adults, but that disgust of others should not prevent the consenting adults from having their sex or love lives. Each of us should stand up for the relationship rights of all consenting adults. The disgusted person is free to not have such relationships, but should recognize that other adults should be free to have orientations, feelings, and relationships they may not understand, and free to express their sexual desires with, and affections for, other consenting adults in the ways they want.

There is no good reason that siblings who are consenting adults should be denied their right to be together however they mutually agree.

Some Exclusive Interviews with Siblings


From Russia With Love (Sister Raising Four Children with Her Genetic Full Brother)

Third Time is the Charm
(Genetic Half Brother and Sister)

The Family Values of Lifelong Love (Brother and Sister, their daughter also gives her perspective)

A Same-Sex Marriage Still Denied
(Male Identical Twins)

In Double-Love But Denied the Right to Marry (Brother and Sister)

A Woman Denied the Right to Marry the Person She Loves (Genetic Half Sister and Brother)

A Slowly Simmered Love (Genetic Half Brother and Sister)

They Would Marry Today If They Could (Genetic Half Brother and Sister)

Building a Family, But Denied the Right to Marry (Genetic Half Brother and Sister)

A burning love denied marriage equality (Genetic Half Brother and Sister)

Genetic Sexual Attraction Sparks an Intense Love (Genetic Half Brother and Sister)

A sister married to her brother in every way but under the law

A brother whose lifelong lover is his twin sister

A man whose husband is his brother

A polyamorous bisexual woman who'd marry her twin brother

A sister who would marry her brother

A brother whose brother is his husband in every way except by law

Another sister married to her brother in every way but under the law.

A Young Woman Denied Her Rights (Genetic Half Brother and Sister)

Another Loving Couple Denied Their Freedom to Marry (Brother and Sister)

Two Women Still Denied Their Right to Marry (Sisters)

Australian Couple Denied Their Freedom to Marry (Genetic Brother and Sister)

A Young Adult Love in Hiding (Brother and Sister)

A Brother Tells of His Marriage to His Sister

Very Happy Together But Denied the Freedom to Marry (Half Brother and Sister)

A Lifelong Love Denied Marriage Equality (Brother and Sister)

Another Marriage Denied Equality Under the Law (Brother and Sister)

A Beautiful Woman Denied the Right to Marry the Father of Her Children (Brother and Sister)

Kevin and Donna (Brother and Sister)

Interviews By Others

The Final Manifesto published an interview with a woman who wants to marry the father of his child, who is her brother.

Jane has an interview with a woman who is with her brother.

Adopted Siblings

A woman who is married to her adopted brother in every way except under the law.

Polyamorous Consanguinamory

A Bisexual Woman Denied Her Rights (A Triad with Male Twins)

Two Women Still Denied Their Right to Marry (Genetic Half-Sisters)

A mother, her son, and her daughter who want to marry

A young man in a polycule with his mother and sisters

A Pansexual Woman Denied Her Rights

A Unicorn Makes Three (A Woman with Her Sister and Son)

If you've been in such a relationship or know someone who has as you would like to be interviewed, I'd like to interview you. Contact me at fullmarriageequality at protonmail dot com.

If you are looking for help, see this page.
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1 comment:

  1. whats wrong with having a child years after the 1st child? nothing’s wrong with that.


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