My son is 35 now.
When he was around two, he had a high fever over a weekend, so we had to take him to an emergency room.
The doctors noticed bruising on his legs, the front of them.
They were in the same area on both legs, between his knees and feet, about 1/3 that way up.
They asked my wife and I where they had come from and we honestly did not know.
They didn't do anything, like take him away, but they did give us some cross-ways looks.
About a week later, when he was feeling better, I took him outside to ride his tricycle.
He didn't quite get the concept, so he propelled it with his feet.
Every other revolution or so, he would bang his shins into the pedals.
That's where the bruising came from.
I taught him to use the pedals that day, and the bruises went away.
I would say it was my fault for not picking it up earlier, but at least we found and corrected the problem.
I'm all for protecting kids, but sometimes, there is an explanation for things that isn't related to abuse or neglect.