I feel like a lot of bullying is caused by lack of family sizes. It's not just having two parents but multiple brothers, sisters, and cousins I feel like bullying is more controlled because if kids are tormenting you family has your back. All these single mom kids without brothers/sisters and no family gatherings feel very alone in the world. In my family I'd play with my friends on Saturday and my cousins on Sunday. If I was down in the dumps one weekend I still had my cousins.