Yesterday my 5 yr old ran away from me on a walk in the countryside after being told off. He was missing for about half an hour and I panicked when a dog walker said she'd seen him walking off with a man she assumed was his granddad. I called the police but before they arrived he was found laughing and hiding. He thought it was a game but I can't believe he went so far and stayed hidden for so long.(He was following the man but didn't speak to him.) I've tried talking to him but he's a typical little boy and doesn't like listening. What do I do now? Punish him? How can I impress on him how dangerous it could be without terrifying him? Any ideas?