If real discipline is necessary, a truly firm tone of voice is usually enough. (wy-os.net)
But here's the thing: Raising your voice all the time can dull the effectiveness of yelling or using a firm tone of voice later on. (verywellfamily.com)
Make sure that all the baby names you are considering sound good in everyday conversation, and when spoken in a firm tone of voice. (cozybump.com)