Hello kiddo! So, there is a thing called cousin marriage, which means when two people who are cousins get married. In the United States, each state has different laws about cousin marriage.
In some states, it is completely legal for first cousins (those who share the same grandparents) to get married. In some other states, it is illegal and considered a crime. Some states allow cousin marriage only if one of the cousins can prove that they cannot have children.
Now, why do some states allow it and why do some states prohibit it? This is because some people believe that marrying your cousin can increase the risk of genetic problems in their offspring. Genetic problems are things that can make a person sick or make it difficult for them to do certain things like see or hear properly.
However, there are others who argue that cousin marriage is no more dangerous than any other form of marriage, and that it is a personal decision that people should be allowed to make on their own.
In summary, cousin marriage law in the United States varies from state to state and is a highly debated topic. But remember, whatever people decide, we should respect their choices and always love our family, no matter what!