In embodiments, a Wearable Cardiac Defibrillator (WCD) system is configured to be worn by an ambulatory patient. The WCD system includes a main user interface (UI) output device that can output an image, sound or vibration as a main message about a condition of the patient or the WCD system. The patient may further carry a peripheral device that can also output an image, sound or vibration as a peripheral message about the condition. The peripheral message may mirror the main message at least in part, amplify it, and so on. The availability of the peripheral message provides the patient with the opportunity to better perceive the main message, and the flexibility to receive and react to it discreetly, learn more about the condition, and so on.