Cousin marriage laws in the United States vary considerably from one state to another, ranging from cousin marriages being legal in some to being a criminal offense in others. However, even in the states where it is legal, the practice is not widespread. Several states of the United States prohibit cousin marriage. Data on cousin marriage in the United States is sparse. It was estimated in that 0.
Pennsylvania just became the third state to ban child marriage
Child Dating Laws and Ages | Legal Advice
In the United States , the legality of incest varies widely between jurisdictions regarding both the definition of the offense and penalties for its commission. In all but two states and the special case of Ohio, which "targets only parental figures" ,  incest is criminalized between consenting adults. In New Jersey and Rhode Island, incest between consenting adults 16 or over for Rhode Island, 18 or over for New Jersey is not a criminal offense, though marriage is not allowed in either state. New Jersey also increases the severity of underage sex offenses by a degree if they are also incestuous, and criminalizes incest with year olds the normal age of consent in New Jersey is Ohio allows incest between consenting adults only when one party is not a parental figure see table below to the other. As of [update] , cases of incest involving consenting adults are often not revealed to outside parties, and therefore prosecutions of these cases do not frequently occur. Cases of parent-adult child incest exposed to law enforcement are usually uncovered by another parent.
Policies & Laws
If you're concerned about breaking laws on underage dating, the first thing to know is that no such laws exist. However, you should be aware of statutory rape laws if you're dating someone younger than the legal age of consent in your state. Such laws are there to punish adults who take sexual advantage of minors. If your date is below the legal age of consent, you could be charged with statutory rape, even if the sex is consensual.
Do you suspect that a child or elderly person is being sexually abused? Even if the crime took place years ago, there may still be time to prosecute. Find out if your state blocks rapists from asserting parental rights, such as custody and visitation, over children conceived as a result of dating crime.