I was playing with football with my two nephews, just throwing the ball around, and I threw the ball too high and hard for my younger nephew. It sailed past him and nailed the neighbor's car behind him, and left a dent in the door. I felt so stupid having to go up to their house and tell them what happened..
Oh no!  My gut feels sick for you having to go through that.  It happens to all of us but its so painful and awkward.  How did the neighbors take it?
They were pretty respectful and understanding, and realized that those things just happen, especially when kids are involved. They appreciated that I came and told them right away. Mostly it was because the dent isn't that serious and they feel like they can get it out without much problem. But yeah, I'm glad I don't have a jerk for a neighbor who would have blown up
Its so commendable that you went over and told them right away.  Not everyone would do that.  Your actions increases my faith in the goodness of people.