Stepchildren are minors whose biological parent marries a person who isn't the child's biological parent. The stepparent is the person who is married to a person who has custody of a minor child. Laws governing rights of stepchildren vary by state. State laws govern the rights of stepchildren to inherit property when a stepparent dies without a will, the child support obligations of the stepparent, and other issues.
Federal laws defining a family or household do not apply a consistent definition of stepchildren as family members. Treatment of stepchildren for purposes such as federal taxes and program eligibility varies according to the applicable law.