The responsibilities of a stepparent depend on state law. A stepparent usually is not required to pay child support for a spouse’s child from another marriage, unless the stepparent has adopted the child. Until then, the child’s biological parents are liable for the child’s support. Some states, however, make stepparents liable for the stepchild’s support as long as the stepparent and stepchild are living together.
A stepparent who does not adopt a spouse’s child normally may not claim custody of the child if the marriage ends in divorce, although some states allow a stepparent to seek visitation.
A stepchild usually does not share in the estate of a stepparent, unless the stepparent has provided for the stepchild in a will. However, an unmarried stepchild under eighteen may receive supplemental retirement benefits or survivor’s benefits under Social Security.