Answer: Step-parent
Explanation: Step-parent could be the step-mother or step-father of a child, if the biological parent of the child goes into another marriage. A step-child to their biological mother's new spouse with the man being the step-father and also a step-child to their biological father's new spouse with the woman being the step-mother.
In the scenario above,All of Laura's four daughters are step-daughter to Craig who his Laura's new spouse with Craig being the step-father to all of Laura's four daughters.
