What Are The States Where You Can Marry Your Sibling? (A comprehensive list)

In this brief guide, we will discuss what are the states where you can marry your sibling, and look at this taboo subject and why it may be problematic.

What Are The States Where You Can Marry Your Sibling?

There are some states where you can marry your sibling, but most of those states deem marriages between half blood or whole blood relationships illegal, and there are penalties if one engages in these relationships.

There are some states, like Alabama, where it may be legal to marry your second cousins or brother or sisters as long as there is no consanguinity.

Consanguinity is a concept that refers to the common link that exists between individuals because they share genetic material or are related by blood, and the primary reason these marriages and relationships are illegal is because the presence of consanguinity makes the relationship likely to produce children with genetic defects.

According to the genetic sciences, there are dominant genes and recessive genes, and both parents supply one gene to the child which can either be dominant or recessive.

When 1 dominant and 1 recessive gene comes together it creates whatever trait or condition the dominant gene contains, in the child, while the recessive is suppressed.

However, when 2 recessive genes come together in the same person, it makes the condition that the recessive genes contain manifest in the child.

Recessive genes often contain conditions that may cause disorders and problems in the progeny, and when the parents are related, it causes the possibility of recessive genes being passed to the child very high, which means that the risk for genetic disorders increases.

This is the chief reason that it is not legal for siblings to marry in most states, because they might pass on conditions they don’t have but for which they carry the genes to any progeny that comes about as a result of such a marriage.

However, there are still countries that allow for the marriage of siblings, and states in the United States as well, provided that one of them is adopted. In Vietnam, for instance, if a child is adopted for the specific purpose that they will marry their sibling, such a marriage will be legal.

What are the states where you can marry your first cousin?

The laws are more permissive where cousin marriage is concerned, because there is a higher likelihood of the progeny being healthy in these cases, therefore, the marriage between first cousins is allowed in as many as 24 states in the United States.

Some of these states are:

  • Alabama
  • Alaska
  • California
  • Colorado 
  • Connecticut
  • District of Columbia
  • Florida
  • Georgia
  • Hawaii
  • Maryland
  • Massachusetts
  • New Jersey
  • New Mexico
  • New York
  • Rhode Island
  • South Carolinaes
  • Tennessee
  • Vermont
  • Virginia

There are other states that put conditions on the marriage of first cousins as well, for instance, Maine, where the individuals need to meet with a genetic counselor or a geneticist and provide proof of the genetic makeup so that it can be ensured that the risk of having children with genetic problems is minimised.

In Wisconsin, first cousins can be married only if the woman is at least 55, or either is permanently sterile, and in Arizona, the law dictates that first cousins can be married only if both parties are 65 or older, or one is infertile.

Similarly, in Utah, first cousins can marry if both parties are 65 or older, or both are 55 or older with a district court finding of infertility of either individual, while in Indiana, first cousins may marry only if they are 65 or older.

It is possible that these age restrictions exist to ensure that the cousins marry only if they need a partner and are okay with marrying for that reason once it is a given that they will not have a child with similar genetic material.

In Minnesota, first cousins can get married only if both parties are 50 or older, or one is infertile.

How common is it for brothers and sisters to experiment?

Cousin marriage is legal in many countries and states, as we just discussed, but usually, the concept of brothers and sisters experimenting is usually extremely taboo in many societies and cultures, and even though it may be statistically common for brothers and sisters to experiment.

Usually the conditions of brothers and sisters experimenting are quite quite hidden, or at least they used to be, before the prevalence of indecent web content that is centered around the concept of relationships between step sisters or step brothers, or even step fathers and step daughters.

intimate attraction between people who are related is usually uncommon, but that does not mean that it is uncommon for brothers and sisters to experiment, but there is a hypothesis that people who live together through the formative years may become desensitized to each other in terms of intimate attraction and this hypothesis is known as the Westermarck impact.

Despite this hypothesis, it has been seen that kin members who are separated at birth may feel intimate attraction towards each other owing to the fact that they have always lived away from each other, and therefore they don’t have the kind of relationship that other brothers and sisters have had the time to develop.

Additionally, sometimes brothers and sisters experiment due to them meeting only once in a while, or in cases where the parent is not the same, that is, step brothers and sisters, which is also considered legal in many places, and states in the United States.

A study done in New England indicated that generally 10% of guys and 15% of females had been involved in or experienced some type of intimate contact with a sibling or sister, and the most well-documented instance in this behavior was usually stroking of genitalia.

If you have children and you are concerned about the instances of brothers and sisters experimenting with each other in an intimate manner, you need to know that a lot of children do so because they are trying to understand intimacy and not because they are attracted to each other.

In this case, you need to make sure that the children understand the gravity of intimate attraction and intimacy, so that they don’t engage in relationships that will change their lives for good if they go too far.

The way to do this is to ensure that they have education about intimacy at the right age, right before puberty, or when if you ever see the brother and sister experimenting, and removing the mystery from intimate relationships.

It has also been seen that brothers and sisters experiment more often when intimacy is a taboo topic in the household or there is extreme distance between the family members, which keeps them from forming healthy familial relationships.

I got my sister pregnant, what to do?

The difficult thing about relationships between brothers and sisters is that there is a likelihood that the girl might become pregnant and then the individuals need help, and therefore you need to consider the possibility that you need to tell your parents, especially if you are underage.

When someone gets their sister pregnant the last thing they think would help is telling their parents, because they would be sure that that would lead to more problems, but the truth is that a botched abortion or complications from the pregnancy or them finding out some other way would likely be much more devastating.

It will be tough telling your parents, but even though they will likely be angry about it they will eventually need to get started on fixing things, and they will want to help you after they are done being angry.

The physical relationship between sister and brother or two sisters may happen during childhood or early adolescence as a result of intimate curiosity, puberty, and confusion regarding their growing bodies and the experience of pleasure, but because there is a possibility that the girl has reached puberty, there can be a pregnancy.

This type of feelings regarding intimate behavior may develop between a brother and a sister between the ages of 9 to 16, and if it has resulted in a pregnancy, here are some ways to talk to your parents about it:

  • You can tell them that you weren’t trying to be reckless
  • Tell them that you are ashamed that it happened
  • Don’t expect them to be lenient
  • Spend time away from your sister and get perspective, once the situation has been resolvedTalk to your sister about how she wants to do it
  • Tell them that you will never do it again and your weren’t thinking straight
  • Listen to them and take their advice about what they say
  • Be strong
  • Apologize to your parents profusely 


In this brief guide, we discussed what are the states where you can marry your sibling, and looked at this taboo subject and why it may be problematic.

This subject is a difficult subject to understand, and there are still parts of society that don’t properly understand the problems with it, while there are other parts of society that validate it completely, by making it legal and totally normal, and this discrepancy alone speaks volumes about how divided the society is on this topic.

If you have any questions similar to “what are the states where you can marry your sibling?”, or other comments related to what we discussed here, please feel free to reach out to us at any time.

Frequently Asked Questions (FAQs): What are the states where you can marry your Sibling?

What country can you marry your sibling?

You can marry your sibling in countries like Belgium and Brazil, and though there are many more countries like that, these top the list.

Can you marry your sister in Alabama?

Yes, you can marry your sister in Alabama, which is something that is quite common knowledge.

This kind of marriages have been considered legitimate in Alabama forever, and the Issue of this type of marriages not deemed illegitimate and also, the issue of any such marriage, before it is annulled, is also not deemed illegitimate.

Which country allows brother can marry sister?

Taiwan is one country that allows brother to marry sister, although there are others like it too, but one needs to know that in this case, Taiwanese law says that at least one of the siblings must be adopted and must not be biological siblings. There is also the addendum that the purpose of the adoption had to have been to encourage the siblings to marry eventually.

Can you marry your step-sister in the US?

Yes, you can marry your step-sister in the US because there is no law that makes it illegal for step siblings to become lawful husbands and wives. 

Even if the individuals are related through their parents’ marriage but not by blood, they are not subject to consanguinity laws which are the reason why marriage between siblings who share the same parents by blood are illegal, therefore, they can get married if they should so choose.








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