My friend sat down and ordered a stiff drink. “I need your help,” she said. “My sister has a brain tumor. I don’t know what to do.”

Three years ago this month, I learned I had bone cancer. That diagnosis led me down a dark year that included chemotherapy and surgery to reconstruct my left leg.

At the time, my wife, Linda, and I were the parents of 3-year-old twin girls, and we were often overwhelmed with the everyday challenges of having a sick dad, a working mom and two preschoolers. We survived with help from many people. But as my friend’s query suggested, some gestures were more helpful than others, and a few were downright annoying. So at the risk of offending some well-meaning people, here are Six Things You Should Never Say to a Friend (or Relative or Colleague) Who’s Sick. And Four Things You Can Always Say.

First, the Nevers.