Just wanted to thank you again for all your advice re: the neighborhood boy on the scooter, and give an update....
After speaking with someone else in the neighborhood, I have decided not to approach the parents at this point. As a few people here suspected, the child in question seems to have behavior difficulties with individuals besides me, and I am led to believe the parents are less than receptive to comments about it. Sad, really. My current game plan is to avoid that street unless I have someone with me, so they may act as a witness as well as to help run interference with the dogs and the scooter. Preferably Mr. Gemini. I'm now doing a little zig-zag route to cut that street out of our way home. If this happens again and I have a witness, I will attempt to speak with the parents.