Vanity

For no reason, she started whining and crying (which happens quite a lot these days).

I took out the camera, and snapped a few shots of her crying. Showed her the pictures and asked. "How do you look when you cry? Ugly?"

She looked at the pictures. And she stopped crying.

I guess I don't have to lecture, scold or any other punishment. Will try this tactic again next time, which I bet is soon.