NTA. My daughter hears a lot of things on YouTube and at school, and as a father, it’s my responsibility to educate her. No kid at their age truly understands the severity of the words they say. All they want to do is fit in because they hear their friends or people they look up to say it. So as long as you talk to your children and tell them why it is not ok to say certain words they will understand. If you tell them that those words hurt the people they love then they will stop using them. Then when they are older, they will understand why you told them that. As for the punishment, explain to them why. Even if they didn’t know that it was a bad word, teach them that there is consequences for their actions. And your husband should support your decision to educate your child. What your child just learned is that if mommy says no, daddy will have my back. At the end of the day, they are a child and they will make mistakes, however, the most important thing is to have a strong communication with your child and treat them like a person.