If someone’s child is behaving inappropriately and their behavior directly impacts you, handle it like you would if it was anyone else. Explain to the Black norwegian elkhound I didn’t fart my butt blew you a kiss shirt Apart from…,I will love this child that you do not appreciate being spoken to a certain way, or that they are in your way and would they please move; whatever the case may be. The fact that it’s a child does not mean you have to make it a teaching moment or impose your values on them. Nor do you have to get their parents involved and question their parenting. Handle the situation and move along. I was in a restaurant with my daughter eating dinner. There was a very large party there at the same time, and they had a little girl with them, around 5 or 6 maybe, who was basically running amok in the restaurant, and none of the adults in the party seemed to care. I kept my opinions to myself. But then the little girl decided she wanted to get a better look at my daughter, who was about 18 months old at the time, and she climbed over the back of the booths and slid in to sit at our table. I calmly looked the little girl in the eye and said, excuse me, but my daughter isn’t allowed to behave that way, so would you please go and do that somewhere else. She did. No disciplining. No reporting her to her parents. Problem solved. And if you do intend to stay with this woman, you need to listen to her and clear up what the rules are regarding her children. Teachers have rules that their students are expected to follow, and consequences for violating them that are written down and agreed upon by the parents. If you want to take on that kind of role you need to sit down with your girlfriend and hash out what the expectations are, not ask the internet how to deal with her children. I think there are several disturbing aspects of this question, many of which have already been mentioned. The utilitarian idea that there is a social optimum when it comes to the allocation of peoples’ talents and that it should be achieved through some kind of top down imposed social engineering is particularly nasty, and goes against the values of individual liberty that are foundational to America.