Place potatoes in a small saucepan and cover with water. Bring to a boil. Reduce heat; cover and simmer for 10-15 minutes or until tender. Drain and cool.
Cut eggs in half lengthwise. Remove yolks; set whites aside. In a small bowl, mash yolks. Add the potatoes, mayonnaise, relish, mustard, salt and pepper; mix well. Stuff into egg whites. Sprinkle with parsley. Refrigerate until serving.