Have you ever not recognized your child (or child you babysit) because of how dirty they are?

I nanny for a little boy who I have know for the past 4 years. I took him to summer day camp today. I was told the theme was beach day-" fun water activities and also learning about the environment." I thought that meant they would swim in the pool and learn about the ocean. He was wearing blue jeans and a white shirt and has blonde hair. As I was waiting in the pickup lane I saw the grubbiest child imaginable- grey tshirt, black jean and brown hair (and no it wasn't wet!) It took me about 5 minutes to realize that was my kid! He was covered in MUD! I had just got my car detailed to boot. Apparently beach day was go down into a muddy creek and try and catch frogs, and other insects and then they had a mudslide for the kids. It was just WOW! he was so dirty I didn't even recognize him- anyone have a similar expirience?