Smoke

 My sister no longer smokes. For a time she smoked heavily. She and her youngest son lived near me. He spent a lot of weekends at my house. I was happy to have him.

My nephew was in middle school. He and my oldest son were out shopping together one day. My nephew had a confession to make.

He was in danger of being expelled from school. One of his teachers had him called to the principal's office. The teacher accused him of smoking.

The thing is that my nephew has never smoked. He did not want to hurt his mother's feelings so he did not tell her.

My sister's smoking was leaving a strong smell of smoke on everything in her house including her son's clothing. That smell made the principal threaten him with expulsion.

My son told me what his cousin had said. I said I would take care of it.

I went to my sister's house. She is a good housekeeper. She loves her sons and is a good mother. However she kept her home closed and no fresh air flowed through. 

I told her what was happening to her son at school. Of course she was horrified. A smoker does not know how the smoke smells or how strong it can be.

So my sister stopped smoking. She aired out her house. She cleaned all the surfaces she could clean. She washed all their clothes.

My nephew had no more problems at school. He still does not smoke.