On the subject of interrupting, a strategy I used with a former boss was to go back to the point where he butted in, then continue from there. Most times, he'd got it wrong what I was going to say. He had good grace to apologise for interrupting, then next conversation he did it again

Family don't tend to do it very much. My aunt does occasionally but only because she's slightly deaf. My brother does, when he's in "dinosaur mode". Doesn't wait for you to finish comment/sentence before butting in with his derogatory comments. I used to let him have his moment, not any more