I have a family of four, work from home sometimes, but find it hard to have kids respecting your workspace because you're "home" after all, so why not barge in? My wife has trouble with boundaries too on that issue. It's a normal problem for people who don't "get" IT/WFH. You're home so.... we can bother you, right?

Lots of people have these problems. It's super common because the idea of working from home and being unavailable is inherently pretty odd for those who don't quite get how context-switching is an extreme productivity killer.