If you have a stepchild, you may have trouble sneaking up on their dirty behavior. While most biological parents feel trapped when their stepchildren act inappropriately, they should realize that stepparents made a conscious decision to create a family. While you may not be able to change their behavior immediately, focusing on the "why" can help you feel less frustrated and helpless. You can even try sneaking up on their dirty behavior from the outside by using one of the methods outlined below..