It's the Most Wonderful Time of the Year...until the Lego Ninja ends up in the neighbor's monkey grass

So the Thanksgiving festivities came together seamlessly, the leftovers have been devoured, and we were thoroughly enjoying our weekend; until Sunday morning. My husband is in the yard and my son is playing basketball in the driveway with a neighbor's child from a few doors down the street. Suburbia at its finest. The basketball game ended and the other child had a Lego Ninja of my son's. Then threw it in the neighbor's yard. Into a sea of monkey grass. I pull up from Christmas shopping around this time. Neighbor devil spawn BOLTS. Son comes to the car door about to cry and tells me what happened. I start to fume, then remember that burning his house down come sunset is probably too obvious. My son walks up to the boy in his yard now, of course, and asks him to come help him look for the toy. Neighbor dad encourages this plan. Neighbor boy comes and stands around as the rest of the Ninja search party crawls around on hands and knees(on the ONE weekend this neighbor hasn't been blowing leaves at 6:45 am) to no avail. We've explained countless times that this wasn't nice behavior and to think about how he feels now and how rotten it would be to ever intentionally make someone else feel this way. It works, but I might have to secretly slip this in neighbor boy's backpack on the way to the bus in the morning: