Families grow in many ways.
You get new kin when people marry. These are your in-laws. They are your new family. This helps us all stay close. Do you have in-laws?
Families grow in many ways.
When people marry, they get new kin. These are called in-laws. You might have a mother-in-law. You might have a brother-in-law. This is called affinity. It is a social bond. It is not a blood bond. Some people also use this for step families. Laws can change how these bonds work. Some bonds end if people divorce. These rules help people know their family. It is a way to stay connected.
Families grow in many ways. When people marry, they gain new kin. These relatives are called affines. Most people call them in-laws. You might have a mother-in-law or a brother-in-law. This bond is called affinity. It is a social bond. It is not a blood bond. Blood bonds are called consanguinity. Affinity is different because it comes from marriage. It can also include step families or adoption.
Laws use affinity to set rules for marriage. These rules change from place to place. Some rules are based on religion. In some places, affinity ends if a couple divorces. In other places, the bond stays. Laws may stop certain people from marrying. They may also stop certain people from having sexual relations. For example, South Africa has rules for close kin. Brazil has rules that stay even after a divorce. In Michigan, laws cover relations up to the third degree. New Jersey has similar rules for certain people. These laws help define how families work in society.
Affinity is a special way that people become family. It happens when two people get married. This marriage creates a bond between one person and the other person's family. This bond is not about blood or genes. Instead, it is a social or moral rule. People call these new relatives "affines." Most people simply call them "in-laws."
How these relationships work can change quite a bit. Some rules about affinity stay the same for a long time. Other rules might end if a couple gets a divorce. Sometimes the bond might even end if a person dies. In some cases, affinity also includes step-families or people who are adopted. These relationships are often treated like blood bonds in the law. This helps define how different families are structured in society.
Laws use affinity to make rules about marriage and behavior. These rules vary depending on where you live. In the past, many of these rules came from religious laws. Today, different countries have different ways of measuring these bonds. They often use something called "degrees of relationship." For example, a husband's relationship to his sister-in-law is a second-degree bond. This is the same level as a wife's bond to her own sister.
Different places have very specific rules about these connections. In South Africa, laws stop certain sexual relations within the first degree of affinity. This involves direct ancestors or descendants of a spouse. Brazilian law has very broad rules for marriage and family. It covers parents-in-law and children-in-law even after a divorce. In Hawaii, breaking rules about close affinity can lead to five years in prison. Michigan and New Jersey also have laws regarding third-degree relations.
We use the idea of affinity in our everyday words. You might hear someone talk about an aunt or uncle. Sometimes these people are actually related by blood. Other times, they are just close friends of the family. You might also hear the term "cousin by marriage." This describes the spouse of a cousin. Even royalty uses these terms to show family ties. Princess Léa of Belgium is an aunt by marriage to King Philippe.
Affinity is a specific type of kinship relationship. It is created through the act of marriage between two people. This bond connects one person to the family of their spouse. It does not describe the relationship between the two people married to each other. Instead, it focuses on the ties to the other side of the family. While blood relationships are called consanguinity, affinity is a social or moral construct. It is often supported by legal rules within a society.
In legal systems, affinity works by assigning degrees of relationship. These degrees measure how closely two people are connected through marriage. The degree of affinity is often calculated to match the consanguineal level of the couple. For example, a husband's relationship to his sister-in-law is a second degree. This is the same level as a wife's relationship to her own sister. A person's relationship to a spouse's parent or child is the first degree. An aunt or niece represents a third degree of affinity. A first cousin is considered a fourth degree.
These relationships can change based on certain life events. Some laws regarding affinity are permanent for the individuals involved. However, other traditions or customs might end if a couple gets a divorce. In some cases, the affinity bond might cease if one marriage partner dies. Affinity can also include relationships formed through adoption or step-family connections. In many legal systems, adoption and step-relationships are treated as if they were blood relationships. This means they are often categorized as consanguinity rather than affinity.
Laws use the concept of affinity to regulate social behavior. One major use is to create prohibitions on incestuous sexual relations. These laws determine which specific couples are prohibited from marrying one another. These rules vary significantly depending on the jurisdiction or country. Historically, many of these prohibitions were based on religious laws. Today, the specific relationships that are forbidden depend on the local legal code.
Different nations have very specific and diverse legal applications for affinity. In South Africa, sexual relations are prohibited within the first degree of affinity. This involves direct ancestors or descendants of a person's spouse. Brazilian law is also very broad regarding these connections. Under Article 1521 of the Civil Code, marriage is invalid between certain relatives. This includes parents-in-law and children-in-law even after a divorce occurs. It also covers stepparents, stepchildren, and certain former spouses in adoptive families.
Other regions use affinity to define criminal conduct. In Hawaii, marriage or sexual penetration within close degrees of affinity is prohibited. Violators in Hawaii can face up to 5 years in prison. Michigan has laws regarding sexual contact between persons related by blood or affinity to the third degree. In Michigan, this can be charged as criminal sexual conduct in the 4th degree. This carries a 2-year sentence or a fine of up to $500. New Jersey also regulates contact between people related by blood or affinity to the 3rd degree. In New Jersey, these laws apply when the victim is between the ages of 16 and 18.
We use terminology related to affinity in our daily language. In formal law, relatives joined by marriage are called affines. Most people use the more common term "in-law" to describe these people. This is seen in terms like parent-in-law, sibling-in-law, or child-in-law. However, the term is often left out for more distant relatives. For instance, the spouse of a cousin might be called a "cousin by marriage." People also use terms like "aunt" or "uncle" for relatives by marriage. This can even apply to royalty. Princess Léa of Belgium is an aunt by marriage to King Philippe of Belgium.
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