Every adult is required by law to report if they suspect child abuse or neglect. It's not just doctors and social workers and teachers. We're all responsible.

But the end result of that was that this parent, who was already at the end of her rope, became more angry and more agitated and then left with the child.

You know that a spanking is not going to do damage. You may not agree with spanking, particularly in public, ... but you can only do so much, legally.