His mother smiled and said,
    “Yes, that’s right. But you know nothing more about them.” And you have no way of knowing if they are always good or if the neighbor is necessarily bad. Even if you know their names and where they live, they are still not close to you and that is why you need not to trust them completely. When we are together or there is another close adult with you, you can talk to them. Then you can greet them, ask them something or answer a question they ask you.

    If there is an adult next to you whom you trust, you can talk to strangers! Maybe this is my short rule for you - she continued a little bit more seriously - But if you do not have an adult, you shouldn’t do it! Even if it’s someone you meet often and you’re sure he or she is very good. You know, adults shouldn’t talk much to children who are alone! They can greet them, ask them or tell them something quickly, after that they have to leave.

    The children watched and listened to their mother. She sounded worried and serious. They knew her well, and they knew that when she looked and sounded that way, then what she was telling them was really important. Nelly thought that their mother was also worried about the news. Maybe she even had guessed that they’ve heard the news and didn’t tell her.

    “I think I need to tell you a few more rules to remember.” They will always be useful to you. We better write them down. Come on!

    The children brought sheets and colored pencils and made a poster with their mother with important rules. Here’s how it looked like: