Other than seeing harm come to their children, what’s every parent’s worst nightmare? For most, it’s feeling out of control—that helpless, sickening feeling that arises when a child simply refuses to comply, no matter what you do.            The majority of parents only have to deal with defiant behaviour of this caliber occasionally, or as part of a normal developmental phase (such as the rebelliousness that accompanies the preteen years). For others, however, it’s an entrenched part of everyday life.…