First, congratulations on landing your first interview! I also work in detox/addiction recovery, after many years in med-surg, and I can tell you the experiences are nothing alike. That's the beauty of nursing: variety and versatility. As for whether you "should" mention your family's addiction history, it won't hurt if you decide to reveal it. I mentioned my own family history during my interview because I was asked to describe the motivating reason for wanting to work there (beyond a paycheck). I'm interested because I want to understand the addiction process, how dual diagnoses play a part in vulnerability to addiction and relapse, and learn some more effective communication skills in regards to dealing with my own family members. Good luck!