I saw something on Facebook that triggered this, say you're in a park and you see a child, he's almost 5 foot tall and built like a small rugby player, go from having fun to screaming, stamping, throwing himself on the ground, maybe trying to run from his parent or hit his parent. From observing the situation 10 mins previously you're aware he was playing in an entirely ordinary way with a group of similar aged friends for half an hour previously. He's the only child upset, his parent is with him, you're nearby. Your children are in the park too, starting to maybe look over.
Thoughts and actions?