Kid wanders into my office.
Nurse Grumpy: "What's up?"
Kid: (wailing) "I was playing in the sandbox and got sand all over my hands and under my fingernails!"
Nurse Grumpy: "Have you tried washing your hands?"
Kid: "Ummm... No."
Nurse Grumpy: "Go wash them in my sink over there. Use soap."
(Kid washes hands)
Kid: "It's all better now!"
Nurse Grumpy: "Okay, go have fun."
Kid: "I'm going back to the sandbox. What a neat trick!"