How to convince my family not to run the fireplace?
I live with my sister's family. In the winter she loves to turn on the fireplace downstairs, unaware that doing this makes the heat turn off, leaving the upstairs very cold. I get home from work at 8pm, and have to blow hair into my hands all night to keep my fingers and nose warm. It's sometimes too cold to sleep. It's also extremely cold in my niece's room, and the other day I saw one of them crying because she couldn't get warm even under her blanket. But I can't just explain it to them because they think that I don't know anything. Can someone point me to a page or a video that will explain it to them?