The best way to respond to her swinging is to firmly -- not roughly -- hold on to her arm and say something like, "No hitting. I know you're mad, but you cannot hit. Hitting hurts." Your child is not intentionally misbehaving, so it's important that your tone sound firm but not angry. You're teaching rules and limits, not punishing. This response is showing your child that you recognize her feelings are not the problem; what she does with her feelings is the challenge. Your job in these emotional moments is to let your child know what is and isn't acceptable and then to teach her how she can express her feelings in an appropriate way.
After you have stopped her behavior and validated her feelings, you can show her alternative ways to vent. While most parents agree that hitting isn't acceptable, they differ in how they feel anger should be conveyed. Some are fine with their children shouting in the air as loud as they can to get their feelings out. Others suggest stomping feet, scribbling with a red crayon, or hitting a safe object, such as a pillow. It's up to you to decide what feels comfortable. The bottom line is that you're acknowledging your child's feelings and helping her learn nondestructive ways of expressing herself.
Originally published in American Baby magazine, August 2006. Updated 2009