This is the key - separate office. I've been working from home for 7+ years. My wife and I homeschool our 7 kids. They all know when dad is in the office, he's working and the only interruption I allow is a request for a hug. When I take breaks, we have fun, get rowdy, and help with school work and chores. But when dad's in the office, he's working (even if I'm just burning cycles on HN!)