What are the states where you can marry your sibling?

In this article, we will answer the following question: What are the states where you can marry your sibling? We will speak about how common it is for siblings to get married and why this type of relationship is taboo. 

States Where You Can Marry Your Sibling

There are no states where you can marry your sibling, but there are some states where you can marry your cousin in some circumstances, and these are:

  • Alabama
  • Alaska
  • Arizona: Only if both parties are 65 or older, or one is infertile
  • Arkansas
  • California
  • Colorado
  • Connecticut
  • District of Columbia
  • Florida
  • Georgia
  • Hawaii

What States Can You Marry Your Sister?

The States where you can marry your sister, include Alabama, Arizona and Alaska, but even in these states, there are stipulations in the law. For instance, in Arizona, one can only marry their sister if both parties are older than 65, or if at least one of them is infertile. This is because when one marries their sister the risk of genetic disorders in the child increases.

Where you can marry your sibling?

The countries where you can marry your sibling are usually located in the Middle East, and in some regions of North Africa and China. In the United States, blood marriages are still prohibited in 31 states, however, this refers to marriage between first-degree up to the four-degree of cousins. 

With the exception of small regions, worldwide, it is illegal to marry your sibling. 

Can you marry your niece?

No, you cannot marry your niece, unless certain circumstances are true for you. Marriage to one’s niece is known as avunculate marriage, and it refers to a marriage with a parent’s sibling or with one’s sibling’s child. This type of marriage may occur in some parts of the world, but in most places consanguineous marriages are not legal.

Half Uncle and Niece Relationship

A half uncle and niece relationship, or marriage, is known as Avunculate marriage, and it is more legal than some other incestuous relationships. Even though one could be a half uncle, usually they may not be referred to as such, and just be called uncle

No, sibling marriage is not legal in most places in the world, and even though there are many states in the US and countries that allow marriage between brother and sister, they need to be step-siblings or cousins for the marriage to be legal. Sibling marriage is not legal because any children resulting from such a marriage are more likely to suffer from genetic disorders.

No, it is not legal to marry your sister in any state in the US, or in most countries around the world. It is not legal to marry your sister because a brother and sister share genetic material and this makes the chances of their child having a genetic disorder much higher.

Can you Marry your Sister?

No, you cannot marry your sister, as there is a high likelihood of genetic disorders in the children when a brother and sister marry each other. For this reason brother and sister marriages are not legal in the United States. However, one might be able to marry their adopted sister as long as there is no relation whatsoever or their step-sister.

Can siblings get married?

No, siblings cannot legally get married in most places(including the United states), even though cousin marriage is legal in most countries. Avunculate marriage, or marriage with a sibling’s child or a parent’s sibling, is legal in many places, but sexual relations or marriage between siblings is considered incestuous almost universally.

In Spain, intimate relationships with family members is not an act that is considered illegal or punishable in any way. Family members can marry each other as long as they are not members up to a third-degree of collateral kinship. For example, an aunt or uncle cannot marry their nephews or nieces (third grade).

In Portugal, intimate relationships with family members are also not punished, but unlike Spain, marriage is prohibited up to the second degree of kinship. For example, marriage between siblings is not allowed (second degree), but marriage between uncle or aunt with their nephew or niece is allowed (second degree).

In France, marriage is allowed as long as it is authorized by the presidential order and as long as they meet certain requirements, which are that the person with whom they had a previous relationship has died.

Other countries such as Russia, Japan and China, sex between family members is not prohibited, but when it comes to getting married, they do have some kind of restrictions to do it.

One of the countries that have particular characteristics is Sweden, where half-siblings’ marriage is allowed as long as they have a father in common. In addition, they need special permission from the government to formalize it.

In the Netherlands, intimate relationships with family members are not punished, but marriage is not allowed between adoptive brothers or sisters who have blood ties.

To take an example from Latin America, in Brazil it is not punishing any kind of intimate relationships with family members as long as it is not performed with someone under the age of 16, in this case, it is heavily punished.

One of the countries that punish intimate relationships with family members the most is Australia, where carrying out such an act can be punishable by 20 years in prison.

Should intimate relationships with family members NOT be sanctioned?

intimate relationships with family members have always been carried out. From ancient civilizations such as the Roman, Egyptian or Greek where it was a practice that did not “scare” anyone. The practice began to be punished once Roman Law was developed.

This practice is punished only for the purpose of protecting the base of society and protecting families. Thanks to this, it allows identifying the roles of each member of a family. In many families, when there is an intimate relationship with family members, it is not always consented to by both parties. 

In the case of countries where it is prohibited, the victim is afraid to report that the person would also have committed a crime. However, in countries where intimate relationships with family members are not punished, the victim does usually report as she has not committed any illegal activity.

For this reason, all cases must be studied in a particular way so that victims can be protected.

How common is sibling attraction? 

If you investigate the subject beyond the surface, you find that intimate relationships with family members are more widespread than you think and, in many cases, not only consensual but also motivated by the same things as conventional adult relationships: love, need, desire, loneliness and attraction. 

This raises many ethical questions about consent, victimization, legality and morality, but also a very important one: can someone have a healthy, consensual relationship, both sexual and emotional, with a close relative?

It is difficult to persuade psychologists to officially talk about such a thing outside the abusive context because they fear that it would legitimize it and that would undermine the victims of cases of non-consensual intimate relationships with family members. 

But the general opinion is that one of the important factors of consensual intimate relationships with family members seems to be both the fractured nature of modern families and their closeness to other families.

I got my sister pregnant. This is one of the most common reasons some opt to marry because of the sexual attraction one feels for the other.

How common is it for step siblings to marry?

Many cultural taboos are created around genetic problems. There is nothing biologically wrong with two people who were created by completely different parent pairs being attracted to one another.

Social issues could be an entirely different thing. The longer you may have lived under the same roof, the more strange you may be seen by outsiders. I would say that this is entirely curable by moving to a different community, but without knowing how old and independent the parties are, it is difficult to say if this is practical.

So, as with many issues with which people struggle, it may depend on circumstances, but there is nothing morally repugnant about the situation, you simply have to ask what are the consequences in your community and your family?

Why do most people feel the rejection of a sibling relationship, even if it is consensual? 

The answer is it is taboo. In the vast majority of cultures, sexual relations between relatives with different degrees of consanguinity – parents with sons and daughters, brothers among themselves and, to a lesser extent, cousins – are not socially accepted. Sometimes they are also legally prohibited.

One explanation is the rule of exogamy: in the primitive tribes, young people looked for their partner outside the group – in some societies women left and in others, men – and these marital ties favoured alliances with other lineages, which strengthened the family nucleus and reduced the possibility of confrontations with neighbours, but there is also a biological reason. 

When human beings are paired with their relatives over several generations, the risk of inherited diseases increases; individuals become less fertile and reproduce less. In other words, evolution rewards the dispersion of genetic inheritance and punishes its concentration.

An argument that reinforces the biological interpretation is that also some animal species avoid mating with members of their family. In species such as chimpanzees or spider monkeys, females must leave their natal groups when they reach sexual maturity and search for a new one. In the cappuccinos or the macaques, it is the opposite, it is the males that must leave the group. 

An adaptive mechanism that guarantees that this rule is met is the development of sexual rejection towards the people with whom we live; The so-called Westermarck effect is established in early childhood, but, according to some scientists, it would also explain the decrease in desire in long-term marriages.

Suppressing sexual attraction to avoid intimate relationships with family members

But how would you do natural selection to promote avoiding such behaviours? After all, there is no trait by which we can recognize brothers and sisters with the naked eye. 

According to Westermarck, evolution has decided to pull statistics to create a mechanism of aversion between relatives. As people who see each other daily and belong to the same environment during the first years of life have many possibilities of being related, the criterion used to suppress sexual attraction is the existence or not of proximity during childhood.

This predisposition to not be attracted to the people with whom we come in contact periodically during the first moments of our lives would be genetically based and would represent an evolutionary advantage; but as a result of this, we would also have no sexual interest in old childhood friendships, for example.

FAQ about States where you can marry your sibling

Do people marry their step-siblings?

Generally, people can marry their step-siblings, unless the law in their country prohibits it. If step-siblings are not related by blood, they can get married and even have children. However, marriage between people who are related by blood is illegal. 

Can you marry your sibling in law?

You cannot marry your sibling in law, since technically, he/she is married to your sister/brother. However, if this is not the case, you are not blood-related to your sibling in law, thus, you should be able to legally marry them. 

Is it normal to be attracted to family members?

It is not normal to be attracted to family members, however, there are enough cases out there to prove that this happens. There is even a term for this, called Genetic Sexual Attraction, or GSA. 

Why don’t we find our siblings attractive?

We do not find our siblings attractive because we grew up too close to them. The constant closeness leads to saturation of stimuli and too much familiarity between brother and sister, which kills any attraction. This can be seen even in people who are not relatives, but who grow up in the same house.

What is it called when you are attracted to your sibling?

When you are attracted to your sibling, you may speak of Genetic sexual attraction. GSA means that a strong sexual attraction may develop between close blood relatives, but only when the two first meet as adults.


Findafamilyattorney.com – Is it Illegal for Step-Siblings to Marry?

Legalbeagle.com – In What States Is It Illegal to Marry Step-Siblings?

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