Glad your kid isn't hurt. I wrecked once while towing our trail-a-bike. The front wheel slipped off the sidewalk and hit a muddy spot at the same time I tried to steer back onto the sidewalk. Me, my son, and bike went down on the right side. My son was OK, he was ready to get back on the trail-a-bike and ride again, but it bent the derailleur hanger on my bike.