Come to think of it, I did get involved with a neighbor's kid's situation once, though not in a disciplinary way. These two girls (either sisters close in age, or friends - not sure) were going down the street - one on a bike and one on a razr scooter. The one on the razr scooter hit a bump and was thrown a good distance. I heard her screaming and crying outside. I hear that a lot, you know when kids fight over shit. But after the crying persisted for a few minutes, I figured that something was wrong. So I went outside, and the girl had some bad road rash from head to toe. I asked her if she wanted to come in to get cleaned up, but she got scared. I honsetly didn't even think about how scary that could be - when I was 9ish (the age she appeared to be) I would have gone into any neighbor's house. Of course, I knew all my neighbors, unlike here. So, then I asked her if she wanted to clean up using my hose if I brought stuff out to her. I also brought the cordless phone out to her, so she was able to call her house and make sure that there was someone to let her in. We also have a neighbor named Jackie who has kids that are the same age, so I asked if she knows Jackie. She did, and so I asked if she wanted me to get Jackie, since that's a grown up who's not a stranger. She didn't - so she just let me help her clean her scrapes and put bandaids on them.
After that, I just let her go home and made her promise to call her mom or dad. I told her that she should probably put Neosporin on her road rash, but that Neosporin is medicine, and I didn't want to give her medicine without her mom or dad's permission.
So, that was sort of an eye-opening experience for me. I don't have kids and I don't come into contact with them much. It sucks in this day and age that they're fearful of going inside a neighbor's house when they're injured like that. But I guess that for everyone involved it was good that I was just able to bring the stuff she needed outside (phone, soap, paper towels, bandages) so that she could clean up, control the bleeding, and get home.