Would you ever expect your child to pop out of bed, come to breakfast with a smile and good mood, when she is under the weather? If she has a fever of 100' or 101', can you expect her to do her homework well, do her chores without complaint?
Of course not! First you treat the fever. If aches and pains go along with the fever, uh oh, might be the flu. Time for chicken soup, cold compresses, bed rest. Lay low, sweetheart, and let's get you better.
What about when she has an emotional fever? What's that like? It usually comes in the form of upset over things not going right for her, being told "no" when she had her heart set on something, friends not being able to come over, school or friendship or relationship drama. Then you hear attitude, disrespect, and noncompliance.
First, take her temperature. If she has a physical fever, treat the symptoms first. If she does not, then treat the emotional fever. If you come at her with consequence and control because of her attitude and words, you've lost a teachable moment. Empathy for what you think she is feeling, also called Active Listening, is the cure for the emotional fever. As you understand the feelings behind her actions and words, her emotional fever comes down. Only then will she be receptive to changing her behavior.