I was out with my daughter yesterday and she had chosen to wear a buff band as a cap, so fairly clear there was no hair in there. A stranger came up to us and said something like "Good for you, you're such a trooper!" We both stared at her. I was trying to figure out what on earth she was talking about and whether she knew my daughter somehow. I asked what she was talking about and she clearly didn't want to say, but as we were walking away she said, "Both my parents had cancer." I was really startled. I both didn't want to be rude (because she was trying to be nice), didn't want to mislead her, but also didn't want to share information that my daughter considers very personal.